Alberto Dainese bounced back from stomach problems to win stage 17 of the Giro d’Italia in a photo finish as Geraint Thomas finished safely to retain the leader’s pink jersey.

Dainese, who has spent several days suffering with illness, edged out the fast approaching Jonathan Milan by a tyre’s width in Caorle with Michael Matthews a couple of inches further back.

Mark Cavendish, still seeking a first win of the season a couple of days after announcing it would be his last as a professional, had been near the front of the bunch on the approach to town.

But the Manxman lost position on one of two tight left-handers inside the last two kilometres and could not contest the sprint, showing his frustration as he rolled over the line. There should be one more opportunity for a sprint on Sunday’s final stage in Rome.

Thomas was guided into the finish by Ineos Grenadiers team-mate Ben Swift, staying safe to retain his 18-second advantage over Joao Almeida in the general classification, with Primoz Roglic sat third, 29 seconds down.

That means the Welshman will spend his 37th birthday in pink when the race returns to the mountains on Thursday going into the decisive weekend.

“It was an alright day, a little bit of rain but nothing compared to what we’ve had so far,” Thomas said.

“It was a bit of a crazy bunch finish, we’re happy to get that done. We knew the sprint teams would race a decent pace and we were able to save as much as possible for the next three days.

“It will be nice (tomorrow), hopefully it will be a good day. There’s lots of work to do before (Sunday), we’ll take tomorrow first.”

Before the mountains to come, this was a rare opportunity for the sprinters, and their determination to take it was clear as a four-man breakaway that included Charlie Quarterman was offered little margin and little hope, never building much more than a 90-second advantage.

The last of those escapees, Senne Leysen, was caught with five kilometres left of the 197km from Pergine Valsugana, almost all of which was either flat or downhill.

When the sprint began, Matthews struck out first but Dainese, racing close to home in the north east of Italy, used his slipstream to come around to the right.

More of a surprise was the storming finish of Milan, who appeared out of position on the final bend but this Giro’s in-form sprinter had the pace to get within a few millimetres of victory.

“This is insane,” said the 25-year-old Dainese. “The first sprints didn’t go as we planned, we did a good job but we never had a good result to show it…

“In the last metres I was really digging deep. I saw Jonny coming, I couldn’t really throw my bike because I was on the limit but it was nice to get my wheel a few centimetres in front to get the win.

“Especially after the last five days, I was quite sick with stomach issues and also my breathing was not good and today was the first day I was feeling good. I’m super happy, I can’t thank my team enough for keeping me in the race and keeping me motivated.”