As we pick up the action, Joey Rosskopf (BMC Racing Team), Mikkel Frolich Honoré (Quick-Step Floors), Matteo Sobrero (Dimension Data) and Filippo Ganna (UAE Team Emirates) have a lead of just under two minutes over the peloton.
The quartet escaped shortly after the flag dropped in Racconigi. On a day of steady rain in Piedmont, the gruppo was content to allow the escapees a degree of freedom in the opening kilometres. By the time they reached Chieri after 42km, their lead stood at 3:25. Astana took up the reins of pursuit shortly afterwards and their advantage has been pared back accordingly.
Fabio Aru's is the last name on the palmares of Gran Piemonte, but appearances can be deceptive. Last year's edition of the race was combined with the Italian national championships and took place on a hilly course around Ivrea, where Aru soloed to victory. Today's race is on an altogether flatter route, which brings the peloton from Racconigi to Stupinigi.
The race formerly known as the Giro del Piemonte has had a rather flexible identity over the years, with myriad route alterations. This year's course loops around Turin and the event has been dubbed la corsa reale by RCS Sport, given that the castles at Racconigi and Stupinigi were residences of the House of Savoy. For good measure, the course passes through other sites linked to Italy's former monarchy, namely Pralormo, Aglié, Venaria Reale and Rivoli.
110km remaining from 191km
On the approach to Foglizzo, Rosskopf, Honore, Sobrero and Ganna remain just shy of two minutes clear of the peloton.
Thibaut Pinot conquered Superga to claim a fine victory at Milano-Torino yesterday, though neither the Frenchman nor his Groupama-FDJ team are in action this afternoon. "I love racing in Italy, from starting the season with Tirreno-Adriatico and then ending it with Il Lombardia. This final 10-day block of racing that leads to Il Lombardia is my favourite," Pinot said afterwards. Stephen Farrand has more here.
103km remaining from 191km
Rain continues to fall over Piedmont. The escapees have averaged 42.7kph through the first two hours of racing.
97km remaining from 191km
Joey Rosskopf (BMC Racing Team), Mikkel Frolich Honoré (Quick-Step Floors), Matteo Sobrero (Dimension Data) and Filippo Ganna (UAE Team Emirates) are though San Giorgio Canavese with a buffer of 2:30 over the peloton.
EF-Drapac have joined Astana at the head of the peloton and are helping to chase down the four escapees. With Sacha Modolo in their ranks, EF-Drapac have a firm contender in the event of a bunch finish.
86km remaining from 191km
Lotto Soudal hit the front of the peloton in numbers at Feletto, and their forcing has caused a split.
Tim Wellens, Tiesj Benoot, Thomas De Gendt, Jens Keukeleire and Maxime Monfort of Lotto Soudal have been joined by Cyrus Monk (EF-Drapac) and Nikita Stalnov (Astana) in a seven-man group that is now just a minute down on the four leaders.
This quintet of Lotto Soudal riders is eating into the break's margin at an impressive rate of knots. They should soon be upon the escapees.
80km remaining from 191km
De Gendt, Benoot and company have closed to within 10 seconds of the four leaders. They are about to make the junction.
There are now 11 riders at the head of the race, 20 seconds up on the peloton: Joey Rosskopf (BMC Racing Team), Mikkel Frolich Honoré (Quick-Step Floors), Matteo Sobrero (Dimension Data), Filippo Ganna (UAE Team Emirates), Tim Wellens, Tiesj Benoot, Thomas De Gendt, Jens Keukeleire and Maxime Monfort, (Lotto Soudal), Cyrus Monk (EF-Drapac) and Nikita Stalnov (Astana).
72km remaining from 191km
The gap is down to just 16 seconds, but the Lotto Soudal quintet remain committed to their surprise offensive on the front of the race.
68km remaining from 191km
The 11-man move has been brought to heel by the peloton, but this is likely to be but a temporary lull.
And so it proves. Matti Breschel (EF-Drapac) and Marco Marcato (UAE Team Emirates) have attacked from the bunch.
Davide Ballerini (Androni Sidermec) and Andriy Grivko (Astana) have bridged across to Breschel and Marcato, making it a four-man group at the head of the race. Their lead over the peloton is a slender one.
A crash at the head of the race sees Ballerini and Grivko come down, while Marcato is also caught up in the incident. Breschel is forced to press on alone off the front.
56km remaining from 191km
Matti Breschel (EF-Drapac) has opted to commit to his solo effort, and the Dane has a lead of 35 seconds over a peloton that is being led by Bahrain-Merida.
Bardiani-CSF are also prominent at the head of the peloton, doubtless with an eye to Andrea Guardini's finishing sprint. The miserable weather conditions, however, mean that this race might not necessarily lend itself to a bunch finish.
52km remaining from 191km
The race is passing through the northern outskirts of Turin, and Breschel's buffer has dropped to just 13 seconds.
52km remaining from 191km
The race is passing through the northern outskirts of Turin, and Breschel's buffer is being kept under tight control by the bunch.
50km remaining from 191km
Andriy Grivko refuses to be beaten by his earlier crash. The Ukrainian attacks alone from the peloton and sets off in pursuit of Breschel.
48km remaining from 191km
And then there were two. Grivko makes light work of the miserable conditions and he bridges across to Breschel at the head of the race.
45km remaining from 191km
Grivko and Breschel are collaborating well, and their advantage has stretched out to 43 seconds over the peloton, where Bardiani-CSF and Bahrain-Merida are setting the pace in support of Andrea Guardini and Sonny Colbrelli, respectively.
42km remaining from 191km
Matti Breschel can go no further. The Dane sits up and Grivko is now alone at the head of the race. Grivko simply puts his head down and continues to grind his way clear. His lead is 46 seconds.
37km remaining from 191km
Grivko has extended his lead to a minute over the peloton. The Ukrainian is putting in a fine solo effort.
36km remaining from 191km
A crash in the pelootn sees a number of riders come down, including Eduard Grosu (Nippo-Vini Fantini). A race motorbike also went down a little further ahead in what appeared to be a separate incident. The driving rain has made conditions treacherous on this run-in.
34km remaining from 191km
Grivko, meanwhile, has extended his lead to 1:04 over the peloton, where Bahrain-Merida and Bardiani-CSF are still setting the tempo.
31km remaining from 191km
The bunch is strung out in a long line as the pace ratchets upwards, but Grivko is holding a lead of 1:13 out in front.
Speaking to RAI before the start, Sacha Modolo worried that there would be a dearth of teams willing to control the race for a bunch sprint. The EF-Drapac man has caught a break so far, mind, with Bahrain-Merida and Bardiani-CSF doing their bit to keep tabs on Grivko's solo effort.
28km remaining from 191km
Manuel Belletti (Androni-Sidermec) was caught up in the earlier crash but has rejoined the peloton. The Italian was third in the GP Bruno Beghelli at the weekend. Gianni Savio's squad has won the Coppa Italia once again in 2018, incidentally, and has thus assured itself of an invitation to next year's Giro d'Italia.
26km remaining from 191km
Grivko's lead drops beneath a minute as Bahrain-Merida and Bardiani-CSF pile on the pressure in front.
22km remaining from 191km
Two of the most experienced riders in the peloton, Steve Cummings (Dimension Data) and Luis Leon Sanchez (Astana) are parked at the rear of the peloton, happy to leave the fast men to it on a wet finale littered with road furniture.
40 seconds the lead for Grivko as Bardiani-CSF lead the chase. Andrea Guardini is a rider desperate for a victory. He has won just twice this season, both times at the Tour de Langkawi. The Giro d'Italia was to be the centrepiece of his first season at Bardiani-CSF but he abandoned through illness in Sicily in the first week.
20km remaining from 191km
Grivko carries a lead of half a minute into the final 20km of the race. The rain is still falling heavily as the race passes through None.
18km remaining from 191km
Despite the poor visibility on an afternoon that is decidedly grim about the mouth, the bunch can catch sight of Grivko on this long straight. The gap is down to just 26 seconds.
15km remaining from 191km
The rain has abated slightly, but the roads are still very slippery on this run-in to the finish in Stupinigi.
14km remaining from 191km
Grivko surely won't last too much longer off the front. His lead is down to just 14 seconds.
13km remaining from 191km
Grivko is caught by the peloton. Gruppo compatto.
It's a significantly reduced peloton on this approach to the finish. A sizeable number of riders climbed off at the feed, while the delays caused by the earlier crash saw more riders opt to pull out.
10km remaining from 191km
Into the final 10 kilometres. Bardiani-CSF and Bahrain-Merida set the tempo while a delegation from Androni-Sidermec is also moving up.
9km remaining from 191km
Enrico Gasparotto is prominent towards the front of the peloton as he works on behalf of Sonny Colbrelli, who is usually a reliable performer in such miserable weather conditions.
8km remaining from 191km
Gazprom-Rusvelo join the pace-making effort at the head of the bunch.
6km remaining from 191km
Cesare Benedetti hits the front on behalf of Bora-Hansgrohe.
5km remaining from 191km
Bardiani-CSF resume their position at the head of the peloton, with Guardini tucked in carefully in fourth position.
3km remaining from 191km
Julien Vermote hits the front for Dimension Data before swinging over and allowing Bardiani-CSF to resume their pace-making on the front.
3km remaining from 191km
Mirco Maestri leads into the final 3 kilometres for Bardiani-CSF. Colbrelli has slotted himself onto the rear wheel of Andrea Guardini.
2km remaining from 191km
Maestri slides off the road coming out of a corner, but remarkably, nobody else came down. Maestri does not appear to have sustained any injury.
2km remaining from 191km
Quick-Step take over in front following Maestri's crash.
1km remaining from 191km
An attack from a Lotto Soudal rider has sown some confusion in the peloton.
1km remaining from 191km
Jens Keukeleiere (Lotto Soudal) has a small lead coming into the final kilometre, but the bunch is almost upon him.
Keukeleire is brought back and it's going to be a strongman's sprint...
Sonny Colbrelli opens his sprint from distance...
Sonny Colbrelli (Bahrain-Merida) wins Gran Piemonte.
Florian Senechal (Quick-Step Floors) was second, while Davide Ballerini (Androni-Sidermec) took third.
Colbrelli opened his sprint with more than 300 metres to go. Despite making his move from so far out, the result was never in doubt and he was a convincing winner.
Sonny Colberelli reacts to his victory in Gran Piemonte: “The team worked really well in the last 80km and Kristijan Koren guided me well in the finale. With 350m to go, I decided to go for it. That’s my style, and I just said, ‘if they pass me, they pass me.’ I’m very happy to end this season with a victory. It was very dangerous, there were crashes, but when it’s wet, it’s always like that. I’ve grown a lot again this season. I had a lot of second places but I have reason to be hopeful for next year. My objective for next year is to get a big result at a Classic, whether it’s a podium or win. Winning one would be a dream.”
That was Colbrelli's final race of the season and his fourth win of the year. He claimed stage wins at the Dubai Tour and the Tour de Suisse, as well as the Coppa Bernocchi. He also placed second at the GP de Montreal, Brabantse Pijl and the Coppa Sabatini, and finished third at Kuurne-Brussel-Kuurne.
Thanks for joining our live coverage of Gran Piemonte this afternoon. A full report, results and pictures are here, while Stephen Farrand will have all the news and reaction from the finish.
