Unseeded Swiss Stanislas Wawrinka moved into the final of the Rome Masters on Saturday when top American Andy Roddick retired injured in the fourth game of their semi-final.
Sixth seed Roddick was 3-0 down in the first set when he pulled out, apparently suffering from a shoulder injury.
Wawrinka will meet the winner of the match between Australian Open champion Novak Djokovic and unseeded Czech Radek Stepanek, who stunned world number one Roger Federer on Friday.
On Sunday, Wawrinka will be aiming to repeat the success of Spain's Felix Mantilla, who defeated Federer in the 2003 final to become the only unseeded Rome champion of the Open era.
This year's tournament has been dogged by injuries.
Third seed Djokovic reached the last four when Spain's Nicolas Almagro withdrew from their quarter-final with a wrist problem with the score at 6-1 1-0 in the Serbian's favour.
Almagro had gone through to that stage when Chilean Fernando Gonzalez, last year's finalist, pulled out of their third-round match with a leg injury.