Spanish rider Joaquim Rodriguez strengthened his position as leader of the Giro d'Italia on Wednesday and dedicated his win in the 186km 17th stage here to his great friend Xavi Tondo, who died exactly a year ago.

The 33-year-old Rodriguez - who has never won a Grand Tour - recorded his second stage success of the race, seeing off a group of six riders including his major rivals Ivan Basso of Italy and Canada's former pink jersey wearer Ryder Hesjedal.

However, his thoughts were more about Tondo, who was killed in a freak accident aged just 32 when he was crushed between his car and a garage door at a ski resort in southern Spain.

"It was a very special day for me, a year after the death of Xavi Tondo, who was a close friend," said Rodriguez.

"I knew him since childhood. It is for this reason that I held on to win. Evidently, I dedicate this victory to him."

Canadian threat

Rodriguez also admitted he was fearful of the threat posed by Hesjdal in the battle for overall victory after the Canadian - who is just 30 seconds adrift of him - continued to surprise with a determined performance in this stage.

"Today like a lot of the riders I began to suffer from cramp," he said.

"Now, I think that Ryder Hesjedal is the big favourite. He didn't lose even a second on me today and if the gaps stay the same I won't have a chance against him in the time-trial in Milan (the final stage on Sunday).

"Therefore I have no option but to attack and to try and distance him, if not he will win."

The leading group came together at the Passo Giau, the fourth and final climb of the testing stage.

Defending champion Michele Scarponi was dropped by the group 500 metres from the summit and some 18km from the finishing line and was some 20sec adrift of the leaders. However, he showed great determination in overcoming the cramps he was suffering from to get back to them with just two kilometres remaining.

Basso - a two-time winner of the race - then launched an attack and tried to outsprint Rodriguez, but the Spaniard clung on tenaciously to pass him and take the honours.

The biggest loser of the day was Czech Roman Kreuziger, who started the day in fifth overall but got dropped on the third climb (Forcella Staulanza) and was almost 10 minutes adrift at the summit of Giau.

On Thursday the Giro returns to flatter pastures and a 149km ride from San Vito di Cadore to Vedelago. That will be the calm before the storm as Friday and Saturday's two days are the toughest mountain stages.