We're around 25 minutes away from the riders rolling out of Murten into the neutralised zone.
Today's stage features a second-category climb and a third-category climb with an unclassified climb in between. It looks like a good day for the likes of Sagan, Van Avermaet and Matthews.
Peter Sagan won yesterday's stage, beating Elia Viviani and John Degenkolb in the uphill sprint in Murten. The Bora leader, who now has 17 victories at the race, is also in the race lead. Read our full report of stage 3 here.
Sagan now leads former race leader Kasper Asgreen by 10 seconds. Here's a look at the GC heading into today's stage.
1 Peter Sagan (Svk) Bora-Hansgrohe 7:51:31 2 Kasper Asgreen (Den) Deceuninck-QuickStep 0:00:10 3 Rohan Dennis (Aus) Bahrain-Merida 0:00:11 4 Michael Matthews (Aus) Team Sunweb 5 Lawson Craddock (USA) EF Education First 0:00:16 6 Stefan Küng (Swi) Groupama-FDJ 0:00:20 7 Matteo Trentin (Ita) Mitchelton-Scott 0:00:27 8 Geraint Thomas (GBr) Team Ineos 0:00:28 9 Luis León Sanchez (Spa) Astana Pro Team 0:00:29 10 Winner Anacona (Col) Movistar Team
Today's final climb isn't as tough as the 9% Chuderhusi 20km from the end of stage 2, though it is a little closer to the finish. Nonetheless, Sagan would be expected to hang on to the leader's jersey this afternoon.
The riders roll out of Murten, and start the neutralised zone on stage 4.
The peloton will spend ten minutes riding through the neutralised zone before the race proper begins.
And the real racing is underway as the peloton leave the neutralised zone.
161km remaining from 163km
It's pretty flat for the 80km of the stage, without so much as an intermediate sprint along the way. It's not going to be an action-packed first half of the stage once the break is established.
The first climb of the day, Passwang, comes at 87km. The day's two intermediate sprints come at 122km and 150km, while the final climb to Hochwald comes 15km from the finish.
After 15km we have a breakaway. Robin Carpenter (Rally UHC), Simon Geschke (CCC Team) and Gian Friesecke (Switzerland) are the three men out front. They have an advantage of one minute.
Multiple reports confirm another rider made it into the day's break, though their identity isn't confirmed yet.
Taco van der Hoorn (Jumbo-Visma) is the other man out front.
143km remaining from 163km
After 20km of racing, the break are two minutes up on the peloton.
This quartet is certainly the break of the day – nobody else seems interested in chasing them down or trying to get across at the moment.
Geschke is the best-placed on GC from the break. He lies 49 seconds down and is now in the virtual race lead. The other three men lie over 12 minutes down on Sagan.
128km remaining from 163km
Geschke is very unlikely to be in the real race lead come the end of the stage, of course. The sprinter's teams will make sure of that.
2:20 for the break as they approach the 50km mark.
Yesterday's stage saw John Degenkolb beaten into third place by Peter Sagan in Murten. After the stage he talked about his battle with Sagan for his own leadout man's wheel.
“It was looking really, really good until just before the last corner. I had to fight with Sagan for my own teammate’s wheel and it was super crazy against him. I think it was a little bit over the limit," said Degenkolb. Read the full story here.
The breakaway riders have ten pro wins between them, with only Friesecke yet to take a victory. Geschke, of course, won stage 17 to Pra-Loup in the 2015 Tour de France.
No change in the situation out front for now – the break are still around 2:20 up the road.
The break are around 30km from the first climb of the day, Passwang.
100km remaining from 163km
The break enter the final 100km of the stage. The time gap remains the same.
Actually, the latest info from Jumbo-Visma suggests that the time gap is up to 3:30 at the moment.
Joseba Beloki, the ONCE rider who had his career ruined by a brutal crash at the 2003 Tour de France, has commented on Chris Froome's recent crash and the recovery process.
The now-retired Basque said that the crash will be a "life-changing experience" and that recovering will be a case of "two days forward, one day back. It’ll be hard." Read the full story here.
Omar Fraile (Astana) has hit the deck. Hopefully nothing too serious.
It's still a three-minute gap for the break as they get closer to the first climb of the day.
No updates on Fraile yet. Hopefully it was a minor crash.
80km remaining from 163km
The break hit the first climb, Passwang, three minutes up on the peloton.
Here's a brief clip of the peloton on the climb, courtesy of the Tour de Suisse Twitter feed.
Passwang is 3.6km long at an average gradient of 9.2 per cent, with an average of 13 per cent in the final 600 metres. A tough one to kick off the day's hills.
Live pictures are about to start, so we'll have more information soon.
55km remaining from 163km
55km to race and Bora lead the peloton, 2:33 back on the break.
Van der Hoorn was the first rider over the top of Passwang.
53km remaining from 163km
The break are down the descent and are taclking the unclassified climb to the intermediate sprint now.
48km remaining from 163km
Deceuninck-QuickStep men Elia Viviani and Michael Mørkøv hang at the rear of the peloton as they speed down a descent.
The gap is 2:40 now.
41km remaining from 163km
Carpenter leads Geschke and Friesecke through the intermediate sprint.
Inside the final 40km for the break now as they head down the descent. One climb to race.
31km remaining from 163km
The gap is down to 1:45 now.
An Ineos rider crashes on the descent, along with an Astana rider. It's Geraint Thomas!
Ineos staff are tending to Thomas' head.
The Astana rider was Andrey Zeits.
He has some medical staff with him as well. Both riders are still on the side of the road and there's a stretcher out ready for one of them.
Meanwhile the break pass through the finish line 1:25 up on the peloton. 28km to go.
Thomas looks to have a problem with his shoulder too. His GC hopes are certainly over, and possibly his entire Tour de Suisse.
Here's our story on Geraint Thomas' crash. He's still being treated on th side of the road, road rash to his back and right shoulder.
Up front, the break hits the final cimb, the third-category Hochwald.
Here's an image of the two riders getting treatment.
No word on Zeits yet. We assume he has abandoned the race, as Thomas has.
Zeits left the race on the stretcher, apparently. Fingers crossed that his injuries aren't too serious.
Rider drop from the back of the peloton up the climb, a 3km, 7.5% test.
19km remaining from 163km
Geschke and Friesecke attacked the break. Another strong performance from the Swiss National Team.
Friesecke leads over the top.
17km remaining from 163km
He's 55 seconds up on the peloton now.
There's more climbing now – to the final intermediate sprint.
Daniel Oss leads the peloton, with a host of other Bora riders up there too, along with a few men from Ineos.
Inside the final 15km now, and Friesecke is 33 seconds up the road.
Friesecke takes the bonus seconds at the final intermediate sprint. He's the only breakaway rider remaining.
Patrick Konrad (Bora-Hansgrohe) took two seconds at the sprint, handy for his GC hopes.
11km remaining from 163km
And Friesecke is caught. Sunweb take to the front.
9km remaining from 163km
Sunweb still lead inside the final 10km. They're working for Michael Matthews today.
7km remaining from 163km
Stefan Kung tries an attack but doesn't make any headway.
Matej Mohoric tries too but can't get away either.
5km remaining from 163km
Now it's Mathias Frank's turn to try something.
He gets a small gap but can't get away either. Kung tries again but is unsuccessful.
3km remaining from 163km
3km to go. Bora and Trek lead.
All the sprinters are up there near the front.
2km remaining from 163km
Sagan is on Alexander Kristoff's wheel.
Trek have the most men on the front once again.
Asgreen takes the front for Viviani.
1km remaining from 163km
The peloton hits the final kilometre. Asgreen leads ahead of Trek and then Lampaert, Morkov and the sprinters.
Now Lampaert takes it up for QuickStep.
Viviani is third wheel with Sagan right behind and then Matthews.
A drag race between Viviani and Sagan!
And Viviani is just too fast on the pure flat finish. A win for the Italian!
It looked like Matthews might've snuck into second place ahead of Sagan there. The Slovak threw his bike for the line quite early.
Matthews did indeed take second ahead of Sagan. Trentin was a pretty distant fourth and nobody else was in shot.
It looks like Degenkolb was fifth.
Win number five of 2019 for Viviani, and number 38 for QuickStep.
Sagan retains the overall lead today.
Stage result
1 Elia Viviani (Ita) Deceuninck-QuickStep 3:46:02 2 Michael Matthews (Aus) Team Sunweb 3 Peter Sagan (Svk) Bora-Hansgrohe 4 Matteo Trentin (Ita) Mitchelton-Scott 5 Jasper Stuyven (Bel) Trek-Segafredo 6 Sep Vanmarcke (Bel) EF Education First 7 Reinardt Janse Van Rensburg (RSA) Dimension Data 8 Ivan Garcia (Spa) Bahrain-Merida 9 Stan Dewulf (Bel) Lotto Soudal 10 Fabian Lienhard (Swi) Switzerland
General classification after stage 4
1 Peter Sagan (Svk) Bora-Hansgrohe 11:37:28 2 Michael Matthews (Aus) Team Sunweb 0:00:10 3 Kasper Asgreen (Den) Deceuninck-QuickStep 0:00:15 4 Rohan Dennis (Aus) Bahrain-Merida 0:00:16 5 Lawson Craddock (USA) EF Education First 0:00:21 6 Stefan Küng (Swi) Groupama-FDJ 0:00:25 7 Matteo Trentin (Ita) Mitchelton-Scott 0:00:32 8 Patrick Konrad (Aut) Bora-Hansgrohe 0:00:33 9 Jonathan Castroviejo (Spa) Team Ineos 0:00:34 10 Luis León Sanchez (Spa) Astana Pro Team
Sagan leads the points classification too.
Kasper Asgreen is still the leading young rider. And Claudio Imhof is the mountain classification leader.
There's another chance for Sagan and the uphill sprinters tomorrow though. Stage 5 finishes uphill, and there aren't any tough climbs too close to the finish.
That's all from our live coverage of today's stage. Be sure to tune in tomorrow for more on stage 5!
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