Official results show Contador trailing Fabio Aru by 19 seconds now, with Australia's Richie Porte now more than five minutes down on GC.
Montecchio Maggiore - Jesolo
Giro d'Italia - 22 May 2015
Giro d'Italia – Follow this cycling race live with Eurosport. The action starts at 20:00 on 22 May 2015. Our live coverage lets you follow all the key moments as they happen.
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Confirmation that Alberto Contador has lost a leaders' jersey for the first time in his career. Fabio Aru is the new race leader according to the official results...
It will be a nervous wait until the race commissaires make their decision... Replays show Contador coming down - but not too badly - and then waiting for a team-mate for a new bike. Chris Juul Jensen arrived just in time to hand his steed over - and the Spaniard fought hard to the finish. Porte, on the other hand, was about two minutes down.
Modolo took the win by half a wheel for Lampre Merida - their third of the Giro. Elia Viviani took third place. Greipel not even in the top ten - his train was wiped out by that crash.
Riders coming across the line in drips and drabs - and Contador crosses the line 39 seconds down. If it's judged that the crash came outside the last 3km then the Spaniard will lose the race lead to Fabio Aru.
Sacha Modolo and Giacomo Nizzolo going shoulder to shoulder on this one - and it's Modolo who takes the win!
Only about 20-odd riders left to contest this one. Greipel and Modolo are still there - Viviani too.
So many riders came down there. Richie Porte looks to be involved too. It's hard to see who was not involved - that was right near the front of the pack.
And Alberto Conador is one of the riders down - and that was outside the 3km zone and so any time losses will count.
BIG CRASH: Lots of riders down - and it's outside the 3km point. One rider was pushed onto the verge and hit the deck, causing a chain reaction.
The peloton negotiate the first roundabout without any problems. Alessandro Petacchi is near the front now, as the Lotto-Soudal train edge forward for Greipel.
GreenEdge tucked in behind Trek now, with Lampre Merida moving up.
The pace is fast now as the sprinters' teams edge forward. With so many black rain capes, it's hard to see who's who, but it's certainly Trek taking up the pace-setting for their man Giacomo Nizzolo.
Yes, there are roundabouts, central dividing islands and street furniture aplenty in today's final few kilometres. The question is whether or not one team will come to the fore and boss the approach, or will it be utter chaos?
Contador is still underneath a jacket so we cannot see his pink jersey. He'll be hoping for a safe finish - not guaranteed because there are numerous roundabouts in final few kilometres.
Orica-GreenEdge appearing for the first time so it looks like Michael Matthews will at least have a pop - although the very flat finish is not ideally suited to his strengths.
Handshakes all round from the three breakaway riders as they're caught by the peloton. Time for the teams of the sprinters to start to show their cards...
Tinkoff-Saxo have now come to the front in numbers to keep the maglia rosa out of trouble. Just 20 seconds now for the leading trio.
Still Lotto Soudal lead the chase through Louis Vervaeke. The gap is down to 40 seconds for the three leaders, who are: Rick Zabel (BMC), Marco Frapporti (Androni Sidermec) and Jerome Pineau (IAM Cycling).
We're two and a half hours in and the break is clinging on to a 55-second lead over the pack. 21-year-old Rick Zabel, in his first Grand Tour for BMC, sets the tempo.
The gap has crept up to 55 seconds now, the peloton eager not to swallow up this trio too early. It's wet and windy again. Lotto Soudal, Trek and Giant on the front ahead of Tinkoff-Saxo and Sky.
Change of sun glasses for Luca Paolini, who is clad entirely in non-regulation black rain wear. The only thing that betrays his Katusha roots is his red and blue aero helmet.
The break has one second for ever kilometre remaining. For those of you who are not up to this mathematical conundrum, they have 45 seconds over the peloton with 45km remaining.
The current live standings in the red jersey points competition: 1. Nicola Boem 109, 2. Elia Viviani 94, 3. Andre Greipel 85, 4. Giacomo Nizzolo 84, 5. Philippe Gilbert 83. All five are stage winners this year except that man Nizzolo of Trek Factory Racing. The gap is down to 55 seconds now for the trio ahead.
The riders are passing by Venice airport now. The rain has eased up and may riders are taking off their shoe covers and arm warmers. The gap is still 1:15 for the three leaders. Back with the peloton, it's Cheng Ji setting the pace for Giant Alpecin. Their sprinter is Luka Mezgec, who's had a pretty torrid Giro so far. But he won last year in nearby Trieste - and this is the closest chance he'll get to take a victory near his native Slovenia.
Greipel is one of three riders on this race with over 100 career wins. The others? Alessandro Petacchi and Tom Boonen. The gap is 1:11 for the three leaders, who have been away since the fourth kilometre.
We spoke to Andre Greipel at the start this morning. The Lotto Soudal rider said: "It will be difficult with the rain and slippery roads, perhaps some wind too. Today is an opportunity though so we will try. Hopefully there will be a sprint. My rivals will be Nizzolo, Modolo, Viviani, Petacchi... The priority is the sprint, not the red jersey."
This time Zabel beats Frapporti to maximum points and bonus seconds at the intermediate sprint at Mestre. Back with the bunch, Boem outpaces Nizzolo and Viviani to mop up maximum points for fourth. He won't let go of this red jersey without a fight!
The rain continues to pound down on the break, which rides with a slander 1:15 gap on the Lotto Soudal-led peloton. They are approaching the second intermediate sprint...
Local boy Elia Viviani will have extra motivation to win today with the race visiting his home region. The Sky rider will be one of the favourites alongside the likes of Andre Greipel, Sacha Modolo, Giacomo Nizzolo and Moreno Hofland...
Androni-Sidermec's Frapporti is riding his fourth Giro d'Italia. The 30-year-old has four pro wins to his name, including a stage in the Tour of Britain at Glastonbury back in 2010. He's yet to finish in the top 50 of a stage so far in this year's race. The gap is 1:20 for these three leaders.
Marco Frapporti outsprints Rick Zabel at the first intermediate sprint at Santa Maria di Sala. When the peloton passes through, Elia Viviani is thwarted and can only take fourth - effectively seventh. Nicola Boem, the current red jersey, was in the mix there - knowing that he will struggle against the big guns at the finish.
One minute only for the escapees after that train crossing mishap. If you think he sounds familiar, he is: Rick Zabel is the son of green jersey guru Erik Zabel. This is the 21-year-old's first Grand Tour in his second full season at BMC. He rode Paris-Roubaix earlier in the season, finishing 102nd, and is still looking for a first pro win. He's a gardening expert who loves football, Star Wars and Taylor Swift.
Catastrophe for the break: they have been held up because of a train barrier has come down. They have to wait for the best part of two minutes, practically nullifying their lead. But the pack shows some solidarity and slows down itself when it approaches the crossing. Either way, the gap has come down to 45 seconds now for Pinean, Zabel and Frapporti.
Jerome Pineau is the most experienced rider in this break. The 35-year-old French domestique is riding his fourth Giro d'Italia and won a stage in the cycling hotbed of Novi Ligure in his debut in 2010. The IAM rider's last pro win came in 2011.
The gap is still just above the two-minute mark for the three escapees.
One jersey which will not change hands today is the blue mountains jersey, which Benat Intxausti of Movistar leads. With a time trial on the cards tomorrow, the Spaniard is guaranteed the lead in the mountains classification until at least the end of Sunday's stage in the mountains.
There will be a shake up in the points standings today in all likelihood. Italy's Nicola Boem (Bardiani-CSF) is the current red jersey on 102 points, but he will probably not figure in any bunch sprint and there are 50 points up for grabs. Elia Viviani is currently on 89 points for Team Sky and Andre Greipel is on 85 points for Lotto-Soudal.
The gap is up to almost two minutes now for the three escapees, who will be hoping the peloton makes another hash of reeling in breaks after the calamities of recent days. It'll take something quite extraordinary for there to be no bunch sprint today in Jesolo, mind.
A reminder of the state of the overall classification: Alberto Contador (Tinkoff-Saxo) leads Fabio Aru (Astana) by 17 seconds after his little attack in yesterday's finale. Mikel Landa (Astana) is third at 55 seconds.
CORRECTION: 183 - and not 184 - riders took to the start after Simon Gerrans of Orica-GreenEdge withdrew after yesterday's stage. The Australian crashed badly on one of those slippery descents, and although he soldiered on, he called it a day afterwards. "It's obviously really disappointing for Simon today," directeur sportif Matt White said after stage 12. "There hasn’t been much time for medical staff to assess too deeply yet but the good news is that whilst it is sore it looks to be just some skin off." Gerrans was pulled, though, as a matter of precaution.
The three leaders - Frapporti, Zabel and Pineau - now have 40 seconds over the pack. It looks like this is the start of the day's main break.
Zabel and Frapporti are giving it another go and manage to join Pineau off the front of the peloton. Riccardo Stacchiotti (Nippo-Vini Fantini) and Mauro Finetto (Southeast) decide to try and join the leaders, edging ahead of the pack. But it's no can do for the Italian duo.
Rick Zabel (BMC), Marco Frapporti (Androni Giocattoli), Jerome Pineau (IAM Cycling), Bert De Backer (Giant-Alpecin) and Arnaud Courteille (FDJ) all try to break clear but the move is thwarted by the peloton. Pineau still defies the pack, but the gap is minimal.
Dutchman Stef Clement (IAM Cycling) finished in the gruppetto over 17 minutes down after falling badly in the rain. He races on today despite deep wounds to his elbow and hip.
Three withdrawals from yesterday's stage - all because of those slippery descents in the final third of the race, which cause numerous crashes in the peloton. Jarosław Marycz (CCC Sprandi Polkowicz) went down hard and severely smashed up his face before being taken directly to hospital where he is recovering. Italy's Manuel Belletti (Southeast) and Switzerland's Stefan Kung (BMC) also withdrews after crashes. Kung, who went on the offensive a day earlier, fractured a vertebra in the same incident that saw Marycz hit the deck.
The remaining 184 riders rolled out of Montecchio Maggiore at 1pm UK time. They're all decked out in rain jackets because it's another stinker of a day - and that will affect the time of this short and flat stage, which should be around three-and-a-half hours by my reckoning.
Besides the start - which comes at 50m above sea level - the highest point of today's stage is 31 metres at Vicenza, 11.5km into the race. That sums it up, really. If the average speed is above 50km/h then it will be over in less than three hours.
Hello and welcome to live coverage of stage 13 of the Giro d'Italia - the flattest of flat stages, a zippy 147km schlep from Montecchio Maggiore to Jesolo that skirts the outside of Venice before finishing beside the Adriatic sea.