Dario Cioni again led home Team Sky as Johann Tschopp won the penultimate stage of the Giro d'Italia.

Cioni finished 30th on the 20th stage, six minutes and two seconds behind Tschopp, as home favourite Ivan Basso strengthened his position at the top of the general classification.

2006 winner Basso will head into Sunday's final time trial in Verona with an advantage of one minute and 15 seconds after another strong ride from his Liquigas team helped him cross the line on the Passa del Tonale in third position, 25 seconds behind Switzerland's Tschopp (Bbox-Bouygues).

Another brutal day in the mountains saw this year's Giro d'Italia hit new heights - the riders climbed a total of 6,320 metres during the course of the 178km route from Bormio and also crested the highest summit of the race at the 2,618m Passo Gavia.

That climb came with 50km remaining and it was where Tschopp started to forge clear with Gilberto Simoni (Lampre).

It was Tschopp who claimed the Cima Coppi prize which goes with the race's highest ascent and he then started to put distance between himself and the rest.

Walls of snow at the summit only added to the drama and a flying descent saw Tschopp extend his advantage from the chasing pack which was soon headed by Alexandre Vinokourov (Astana), Valdimir Karpets (Katusha) and Daniele Righi (Lampre).

Not for the first time a late attack from world champion Cadel Evans (BMC Racing Team) further animated the race and the Australian became Tschopp's main threat in the closing stages, eventually finishing 16 seconds behind.

Crucially Basso in the maglia rosa stayed right in touch and came home in third place alongside Michele Scarponi (Acqua & Sapone).

David Arroyo, Basso's closest challenger on the GC, took fifth but has it all to do to make up the 1:15 in the 15km finale in Verona.

Fighting qualities

For Team Sky Cioni produced another good ride in the mountains and he goes into the final day in 17th position on the overall standings.

Michael Barry was 45th on the day and Steve Cummings 58th and afterwards Sports Director Sean Yates admitted he was happy to have got the stage out of the way.

He told us: "It was a very brutal stage and it was a question of getting through it and maintaining positions on the GC which we did.

"Dario produced a good ride, fighting every inch of the way and he remains in the top 20 overall."

Final flourish?

The focus now switches to the final time trial in Verona, with Bradley Wiggins aiming to finish the race on a high.

Yates told us: "Bradley hasn't looked at the course himself yet but the guys who have say it should be good for him.

"We'll take a close look at it tomorrow and we also have a video which we'll be studying on the bus.

"But all the guys are happy to have got this far and will be giving it their best shot tomorrow."