Alpe di Siusi, Italy - Russia's Denis Menchov proved strongest in the ascent of the Alpe di Siusi Wednesday to claim victory in the fifth stage of the Giro d'Italia.

On the day the Tour of Italy celebrated its 100th birthday, Rabobank's Menchov came home in a time of 3 hours, 15 minutes, 23 seconds to finish two seconds ahead of Tuesday's stage winner Danilo di Luca and five clear of Sweden's Thomas Lovkvist.

Seven-time Tour de France winner Lance Armstrong was unable to keep pace with the leaders over the final six kilometres and the Astana rider lost nearly three minutes to his main challengers on the 125km-long mountainous stage from San Martino di Castrozza to Alpe di Siusi.

New race leader Di Luca of LPR Brakes, who claimed overall victory in the 2007 Giro, takes over the leader's pink jersey from Lovkvist thanks to his second-place finish.

The leading trio finished ahead of a chasing group that included Carlos Sastre, Ivan Basso and Levi Leipheimer.

The 92nd Giro continues Thursday with a 248km trek from Bessanone Brixen to Mayrhofen in Austria. (dpa)