Geraint Thomas saw the pink jersey snatched away on the penultimate day of the Giro d’Italia as Primoz Roglic overcame a mechanical problem to win a punishing time trial to the summit of Monte Lussari.

Roglic dropped his chain midway up the cruel concrete road to the top but still had enough in reserve to beat Thomas by 40 seconds, overturning the 26-second advantage the Welshman took into the day.

And that gives the Slovenian a 14-second lead ahead of Sunday’s flat run into Rome, the title his barring any incident.

For Thomas, it dashes his dream of become the oldest ever winner of the Giro in the week he celebrated his 37th birthday.

But for Roglic it was redemption, three years after he lost the lead of the Tour de France one day before Paris on a mountain time trial to La Planche des Belles Filles. He will add the Giro to his three Vuelta a Espana titles.

Within sight of the Slovenian border in north-eastern Italy, Roglic was roared on by screaming hoards of his compatriots.

They had hearts in mouths when Roglic ran over a pothole and dropped his chain. A 16-second advantage over Thomas evaporated but he still had plenty more to give.

“It’s just something amazing,” the 33-year-old said. “It’s not in the end about the win but the people and the energy here. It’s so incredible, really moments to live and remember.

“I dropped the chain, it’s part of it, but I didn’t fear it at all. I put it back, I started and I just went. For sure I don’t want this to happen but I could put the chain back and restart.

“I had the legs and the people gave me extra watts so it’s fine, just enjoying it. There’s one more day to go, one more focus because I think the lap (in Rome) is quite technical. It’s not over until it’s finished but it looks good.”

The stage started in Tarvisio, where a young Roglic once took victory in the Junior World Ski-Jumping Championships, his last victory in that sport before he took up cycling full time.

This 18.6km race against the clock was all about the final climb, 7.4km long at an average gradient of 12 per cent, but starting with more than five kilometres where the average was over 15.

Riders swapped from time trial bikes to climbing machines at the foot, as mechanics followed them up the road on motorbikes with spare bikes over their shoulders, with cars not allowed on the narrow roads.

While Roglic exorcised the demons of La Planche des Belles Filles, this was more heartache for Thomas in the Giro.

It had finally looked like his year. In 2017 his bid for glory was effectively ended when he crashed with a police motorbike on the Blockhaus, then in 2020 he crashed out on stage three when he struck a stray water bottle.

With all that behind him, the 2018 Tour de France winner appeared on course for a second career Grand Tour win as he spent eight days in pink.

“People I know need to stop bugging me, I’m getting emotional,” Thomas told Eurosport after personally congratulating Roglic. “I could feel my legs going a kilometre and a half from the top.

“I don’t want to make excuses but I didn’t feel like I had that real grunt. It was nice to lose by that much rather than a second or two. That would be worse. At least he smashed me.

“Primoz deserves that, he had a mechanical and he put 40 seconds into me. Chapeau.

“If you’d told me in February or March (I’d be second) I’d have bitten your hand off but now I’m devastated.”