As it happened: Victory goes to the breakaway and yellow jersey gains time on chaotic stage 4 of Itzulia Basque Country

Hello and welcome to stage four of Itzulia Basque Country!

Paul Seixas remains in the yellow jersey, and, if he has the appetite, today could be an opportunity for a third stage win in four days. There's more climbing than yesterday, when he went into defensive mode, including a late climb averaging 8% for 3.2km that looks like an ideal springboard.

Alternatively, setting Seixas up for another stage win would involve lots of effort to control the race by his Decathlon CMA CGM team, as there are surely multiple teams and riders who will want to try attacking, and few who believe they could beat the Frenchman in a mano y mano battle. This does therefore seem like a promising day for a breakaway to succeed.

That was the case yesterday, when the bunch gave up the chase to allow the breakaway riders to make it to the finish, with Ineos' Axel Laurance coming out on top. Here's a reminder of how the stage went down.

Itzulia Basque Country: Axel Laurance surges ahead of Igor Arrieta in two-rider sprint for stage 3 victory

Today’s is the kind of parcours that can make for very unpredictable racing - there’s lots of climbing, but not one standout climb in terms of difficulty. Of the seven climbs in total, six of them are rated category three, with just the final one rated category two.

The riders have gathered at Galdakao, and have just set off from the unofficial start.

The peloton is one rider short of those who finished yesterday - Emanuel Buchmann, whose tough start to the season continues.

OFFICIAL START

And they're off!

There have been attacks, but nothing has stuck so far.

The riders are about to start climbing, up the 4.5km, 5.3% Aretxabalgane. That should provide a springboard for strong climbers and puncheurs to try and form a breakaway.

They're on the Aretxabalgane now.

Andreas Kron has used these gradients to attack out the bunch and gain a small lead.

He's been brought, as has every other attempted attacker so far, and the race remains all together.

It's been announced that Roger Adrià has abanoned the race having started today. It's unclear yet why.

KOM - ARETXABALGANE

Bou made sure he was at the front of the bunch going over the climb to increases his lead in the KOM classification, with Pacher and Soler following behind.

The peloton remains together as they descend the climb.

Here is the updated KOM classification:

1 Bou 21 points

2 Seixas 13

3 Arrieta 13

4 Skjelmose 8

5 Baudin 6

6 Mintegi 6

150KM TO GO

Still no breakaway at this point. After descent of this climb comes the longest flat section of the day, lasting about 20km, so the battle to get into the break could rage for some time yet.

A very large group of over 20 riders is trying to go clear. This is developing into a very hectic start!

Pello Bilbao has managed to sneak into this group. He's not too far down on GC, in 13th at 3:42.

That group has been caught - it was too big and unruly to be allowed up the road.

140KM TO GO

Still no break has formed, as the riders continue along this flat section.

Kron is out on the attack again, going clear this time with Alaphilippe and Pericas.

This is looking more promising. The trio are 20 seconds up on the peloton.

Alaphilippe is the eye-catching name in this move. He might have lost the legs of his peak years, but remains a canny rider capable of winning big, as he proved at the GP de Québec last year. Could he make it a fourth French win in four days?

A big group of riders have gone clear of the peloton and are trying to chase the leading trio. There are about 20 riders in it.

130KM TO GO

Tha large chase group has been shut down by the peloton, but Alaphilippe, Kron and Pericas still lead by about 25 seconds.

The peloton has not eased up, and are brining the trio back again. They only have ten seconds as they approach the foot of the day's second climb.

This climb is San Pelayo, the first of five that come in quick succession, and averages 4.4% for 5.7km.

Scaroni, Soler and Garcia Pierna have attacked and are chasing the leaders.

That trio have caught the leading trio, so we have 6 riders leading the race about 10 seconds ahead of the peloton.

Iker Mintegi has also attacked out of the peloton and is trying to join the leading sextet.

Despite looking like a strong group, those riders have all been caught on the climb.

120KM TO GO

So as they approach the top of the climb, the peloton is once again all together.

KOM - SAN PELAYO

Kron managed to stay at the front to take the KOM points at the top of the climb, ahead of Simmons and Vauquelin.

DNF - JUAN AYUSO

There's another abandon to report, and it's a big name - Juan Ayuso.

Having been among the top favourites for the overall title, Ayuso has struggled throughout this race, first being well off the pace in the time trial, then being dropped on the climbs both on stage two and yesterday.

It seems Juan Ayuso was involved in a crash.

There was a split in the peloton on that descent, but the groups have come back together now.

110KM TO GO

The peloton is making it's way up the third climb of the day, the Jata, which rises for 4.6km at 5.8%.

Juan Ayuso, before pulling out of the race.

The riders are over the Jata climb, and Brandon McNulty has gone on the attack, opening up a small lead.

In the absence of their abandoned GC man Del Toro, UAE have been racing very aggressively, nearly winning the stage yesterday with Arrieta and trying to do so again today, with McNulty now and Pericas earlier.

Incidentally, Bou took another mountain point at the top of the Jata climb, reaching the top behind Anders Halland Johannessen and Jardi Van Der Lee.

100KM TO GO

McNulty has a lead of 35 seconds on the peloton. He's looking good, but will surely need some support.

There appears to be a split in the peloton - and Paul Seixas is caught the wrong side of it!

McNulty leads the race as they reach the latest obstacle, the 2.4km, 6.7% Alto de Umbe climb.

It seems that Seixas is safely in the peloton, while chase group has formed behind McNulty and ahead of the peloton.

The peloton is also now a lot further behind McNulty - a whole two minutes, in fact. It seems the American might have succeeded in snapping the elastic.

KOM - ALTO DE UMBE

McNulty crests the climb at the head of the race, while Juanpe Lopez and Gal Gilver were second and third to the top from the chase group behind.

There are a lot of riders in this chase group, but none of the GC contenders appear to have sneaked into it.

The chase group still have 50 seconds to make up on McNulty, but are over a minute ahead of the peloton.

90KM TO GO

Next up for the riders is an uncategorised climb, though it’s pretty much as hard as all those that have come before it already today.

It might be quicker to list who isn't in this chase grop rather than who is. In total, there are 33 riders present.

Some of the names in the group that stand out in terms of potential stage winners are Ben Healy, Tobias Halland Johannessen, Alex Aranburu, Marc Soler, Quinn Simmons, Christian Scaroni and Lorenzo Fortunato.

The peloton is being led b Decathlon, and happy to let this break go. They're 2:20 ahead, but still 40 seconds behind McNulty.

Here is the 33 chase group in full:

Ben Healy, Jardi Christiaan van der Lee (both EF Education-EasyPost), Tobias Halland Johannessen, Andreas Kron, Magnus Cort, Anders Halland Johannessen (all Uno-X Mobility), Guillame Martin, Clément Braz Afonso, Quentin Pacher (all Groupama-FDJ United), Alex Aranburu, Marc Soler, Felix Großschartner (both UAE Team Emirates - XRG), Quinn Simmons, Julien Bernard (Lidl-Trek), Christian Scaroni, Lorenzo Fortunato (both XDS Astana), Steff Cras, Mauri Vansevenant (both Soudal-QuickStep), Juan Pedro López, Raúl García Pierna (both Movistar), Gal Glivar, Emiel Verstrynge, Ramses Debruyne (all Alpecin-Premier Tech), Luke Tuckwell, Haimar Etxeberria (both Red Bull-Bora Hansgrohe), Gotzon Martín, Txomin Juaristi, Jonathan Lastra (all Euskaltel - Euskadi), Tim Rex (Visma-Lease a Bike), Victor Langellotti (Ineos Grenadiers), Bjorn Koerdt (Picnic-PostNL), Fabian Weiss (Tudor Pro Cycling), Carlos García Pierna (Burgos Burpellet BH),

70KM TO GO

That 33-man chase group is two minutes ahead of the peloton, but McNulty is actually growing his lead ahead of them, to 1:35.

McNulty is riding across the finish line for the first time. The obvious thing to do when such a large, strong chase group formed behind him would have been to take it easy and wait to be caught by then, but instead the American has doubled down and is pushing on hard. Surely he can't keep this up all the way to the finish?

Uno-X Mobility are the best represented team in the chase group with four riders, and one of their contingent is pulling the group. They're crossing the finish line, about 1:40 after McNulty.

McNulty is climbing again, up Elorritxueta. At 7.9km it's the longest of the day, but averages a relatively modest 4.4%.

And now the peloton cross the finish, taking it easy at about 3:30 down.

Here was McNulty earlier, when he first broke clear from the peloton.

Decathlon are leading the peloton, setting a steady pace. This certainly seems like it's going to be one for the breakaway, given that almost every team is represented in it.

This is some ride by Brandon McNulty. His lead is still growing, and is now up to 2:15. There’s still over 60km left to ride, but he’s committed to this move, and it’s starting to look like he has a chance.

A small snapshot of some of the 33 riders in the chase group.

KOM - ALTO DE VIVERO

McNulty crests the climb first, but as he was doing so had to change bikes. It was a quick transition, though, and he doesn't seem to have lost much time.

60KM TO GO

As he begins the descent on his new bike, McNulty still has a lead of 2:08 on the chasers despite that delay, and 4:15 on the peloton.

Bahrain Victorious were one of the few teams to miss the breakaway, and are trying to do something about that now as they take to the front of the peloton and up the pace.

The time from McNulty to the chasers is now being reported at 1:45. So his lead has come down, perhaps as a result of that bike change.

McNulty is looking more tired now, churning a big gear as he rides the long flat section that will loop back round for a second ascent of Alto del Vivero.

Bahrain Victorious are still pressing on at the front of the peloton, and that’s the group that’s currently fastest on the road. It’s a big ask for them to bring the race back together, but they’re making inroads, bringing the chase group back to 1:40 and McNulty to 3:20

Bahrain are presumably working for Bilbao, who could launch an attack on either the final climb or subsequent descent. But they also have Antionio Tiberi as an alternative option, albeit he’s lacking his best legs.

McNulty is labouring. His lead to the chasers is down to 1:30, and to the peloton just over three minutes.

This really does look like it's swinging back in the advantage of the breakaway. They're now just 1:40 behind the chasers, and 2:45 behind McNulty.

In theory the chase group should have the biggest advantage, with so many teams represented in it, but the Bahrain-led peloton is putting up a great fight.

40KM TO GO

McNulty's lead continues to fall, down to 50 seconds over the chasers. Uno-X Mobility have upped the pace in that group, and have moving clear of the peloton again, by nearly two minutes.

This flat section has been tough for McNulty, leaving him exposed compared with the protection the larger groups have. Only 30 seconds ahead now, it looks like he’ll be reabsorbed soon.

McNulty has been caught by the chasers, 36km from the finish. He'll drop to the back of the group and have some well-deserved rest.

This is a fierce battle between the breakaway and the peloton, the former still being led by Uno-X Moblity, who appear to be riding for Tobias Halland Johannessen.

Changes in the peloton now as other teams fight for position ahead of the upcoming climb.

Visma and Decathlon are two of the teams up there in the peloton.

Uno-X Moblity lead the break onto the Vivero again. They're going a different way up this time, with much steeper gradients.

Already riders are being dropped out the back of the break, on the lower slopes of the Vivero, including inevitably, McNulty.

Visma-Lease a Bike lead the peloton. Are they trying to tee something up for Tulett?

Attack in the peloton from Florian Lipowitz! Decathlon were alert to the move though and have brought him back.

Attack from Quinn Simmons in the breakaway.

Scaroni, Johannessen and López have gone with Simmons.

Back in the peloton, Decathlon have taken over control again, after being put under threat from Lipowitz earlier.

Ben Healy has been dropped out of the breakaway. That's a surprise, as he looked like one of the favourites for the stage win.

It's all change at the front, and there are now abut eight riders leading the rest of the break.

And it's all kicking off in the peloton! Lipowitz and Seixas have both traded an attack each.

Seixas' teammate takes control of the peloton and calms things down again.

There are now about 14 riders leading the race, the others from the orignial break having been dropped.

Soler is one of those riders still in the front group, and tries an attack.

Soler continues to try to go clear, just 500m from the top of the climb.

KOM - ALTO DEL VIVERO

Soler crests the climb first, but hasn't managed to drop those behind him.

In the peloton, Lipowitz attacks again as they near the summit.

Seixas glues himself to his wheel as they go over the top of the climb, 1:17 after the leaders.

There are about 40 riders left in the peloton, with a few dropped on the climb rejoining on the descent.

Three riders have clipped off the front and now lead the race - Marc Soler, Luke Tuckwell and Anders Halland Johannessen.

They lead the chasers by 13 seconds.

Soler attacks the other two in the fornt group, and is trying to go clear.

Crash for Bagioli, who's up on his feet, but not bac riding yet.

Soler has been caught, and now Johannessen counters.

Soler and Tuckwell are looking at each other, allowing Johannessen to go clear!

Soler and Tuckwell have dropped back to the chase group, who are 15 seconds behind Johannessen, as they approach the final climb.

Johannessen is increashing his lead over the chasers, to 20 seconds.

Meanwhile the peloton is still in contention, at 1:23, but have some ground to make up on the final climb.

Anders Halland Johannessen has started the climb now. This one's a nasty one, averaging 8% for 3.2km.

Soler still has energy to burn, and leads the chase as they begin the climb.

These ramps are horrible They're currently dragging themselves up one that reaches 17%.

Juan Pedro López attacks in the chase group.

Back in the peloton, Primož Roglič is riding at the front.

Johannessen has been caught, by López.

Aranburu also joins them at the front of the race.

Paul Seixas accelerates in the peloton!

Scaroni, Fortunato and Martin have joined the three leaders.

And now Aranburu attacks them.

As for Seixas, his move put others under pressure, but he didn't get a gap.

There are about 15 riders left in the peloton.

The pace is off in the peloton, and Seixas' teammates are rejoining it.

Aranburu leads, with Johannessen chasing him.

10KM TO GO

They're about one kilometre from the top.

KOM - LEGINA

Aranburu summits the climb first, but Tobias Halland Johannessen is bearing down on him.

Johannessen bridges up to Aranburu on the descent.

Fortunato, Scaroni, Martin and López are chasing the two leaders, but are 17 seconds behind.

5KM TO GO

Aranburu has opened up a gap on Johannessen the descent.

As has Paul Seixas in the peloton! It seems we can count descending on the list of things he's already elite at.

Johannessen is back onto Aranbru's wheel as the downhill gradient eases.

They will now take on a short flat section, before the road kicks uphill for the final kilometre.

Behind, Seixas is with Arrieta, and the two have a gap on the peloton.

Aranburu and Johannessenare working toegher and taking it in turns to pace. With a 25 second lead over the four chasers, they're looking good.

Paul Seixas is on a mission! He's catching others from the day's break, and is bearing down on the leaders, just 35 seconds behind.

1KM TO GO

And Aranburu and Johannessen are starting to look at each other as they approach the final uphill. They'll have to be careful not to get caught!

Behind, Seixas is motoring on with four riders dropped from the earlier break clinging to his wheel.

The second group is approaching the two leaders.

Scaroni has gone clear of the other three in that group, and is catching the leading duo.

Scaroni has caught them and is sitting on their wheel.

And now the others from that grup are catching them.

Aranburu launches his sprint...

ALEX ARANBURU WINS

Aranburu holds on for the win. What a chaotic finale!

Johannessen took second, Scaroni third.

Seixas finished 8th, in a group 14 seconds behind Aranburu. That's ahead of the peloton, so he will hae gained some more time.

From somewhere, despite not having been in the days break, Ion Izagirre appeared in the final to finish fourth. He must have escaped out of the peloton unseen, perhaps on the final ascent or descent.

The peloton came home 34 seconds down, meaning all the other GC men in it lost another 20 seconds to Seixas .

There were only ten riders left in the peloton by the end, including all the other riders in the top 6 on GC.

The only riders in the GC top ten who were missing from the peloton were Seixas and Izagirre, who gained time by escaping up the road towards the end,

Where to begin unpacking this stage? It had it all, with non-stop action from pretty much start to finish.

Picking a winner from the giant break that went clear was a fool’s errand, and the balance of power between them shifted right up until the final few hundred metres, when it looked as though Aranburu and Johannessen had allowed the chasers to get back into contention.

But it ultimately turned out that Aranburu and Johannessen played it smart, holding back before launching their sprints and powering away from Scaroni and co to take first and second.

Of the pair Aranburu was the quickest on paper, and so it turned out as he managed to put four seconds into Johannessen in the sprint.

Ion Izagirre has explained the mystery as to where he came from to finish fourth. He went clear with Seixas on the descent, and then, having sat on the Frenchman’s wheel due to his Cofidis teammate Aranburu’s presence up the road, went clear from him in the final 500m.

Alex Aranburu loves Itzulia Basque Country, which, as a Basque, is his local race. Of the ten wins in his career, three of them have been at World Tour level - all of them in this race.

And what about Paul Seixas? It looked like he was happy to play it defensively today, before unleashing his hitherto unknown descending skills in the finale, going clear from the peloton and gaining yet more time. This race has been an exhibition from the teenager, who appears to be able to do it all.

Seixas’s gains means he now leads and Primož Roglič in second by 2:19 and Florian Lipowitz in third by 2:28, while Ion Iagirre has leapfrogged Mattias Skjelmose, Ben Tulett and Alex Baudin into fourth.

Paul Seixas after crossing the finish line, surveying the damage he had done.

Thanks for joining us today, on what was a true barnstormer of a day at Itzulia Basque Country. Paul Seixas’ lead at the top of the GC might seem unassailable, but that isn’t preventing drama and action at this race, with today’s epic fight for the stage win gripping from start to finish.

We’ll be back again tomorrow for the penultimate stage, which also looks like the toughest of the whole race, featuring a total of 3.814m of climbing. With the climbs all distributed across the stage, the stage is set for another thriller - be sure to join us again for all the action.