Novak Djokovic and Stanislas Wawrinka will meet in the final of the Rome Masters after both saw their opponents retire during Saturday's semi-finals.
Unseeded Swiss Wawrinka was on the court with sixth-seeded Andy Roddick for just 15 minutes, when the American - trailing 3-0 - conceded the match due to a back injury.
"I felt something a little bit last night in my back," said Roddick, who had posted a three-set win over 14th seed Tommy Robredo in the quarter-finals on Friday.
"It was a little bit uncomfortable this morning, but I warmed up and it was fine."
"I just made a wrong movement and it went into complete spasm. I can't really move or do much with my left arm. I mean, you can't really play around that."
Djokovic took just 21 minutes to race past unseeded Radek Stepanek 6-0 in the first set, and after losing the first game of the second, the Czech bowed out due to illness.
"I am very sorry, especially for the fans, but I just could not finish the match today," Stepanek said.
"I started feeling bad for the first time after practice this morning and then I ate lunch and was feeling a bit better.
"Once the match started, however, I started feeling worse and worse. I was dizzy and weak and couldn't play. I just need to rest now and recover for my next event."
This was the second successive match Djokovic won via retirement after Nicolas Almagro pulled out of their quarter-final on Friday with a right wrist injury.
"I did not expect two opponents to retire in an event like this," Djokovic said. "But these are the circumstances and this is sport."
"Anything can happen, you know. I think this is another reason and another showing that the season is really tough, especially this year because of the Olympics."
It was not a surprise to see Djokovic in the final, as the 20-year-old is ranked third in the world and also the reigning Australian Open champion.
The same can not be said for Wawrinka, however, who is the first unseeded player to advance to this ATP Masters Series final since Felix Mantilla - who beat Roger Federer in the 2003 championship.
An improbable finalist in a draw that had nine top 10 players participating, the 22-year-old Wawrinka is quickly making a name for himself.
He reached the semi-finals in Barcelona last weekend and his effort here - which includes wins against 18th seed Andy Murray and former world number ones Marat Safin and Juan Carlos Ferrero - has guaranteed him a spot in the top 20 on Monday.
Wawrinka may get a sense of deja vu when he faces Djokovic in Sunday's final.
He captured the lone title of his career in 2006 on the claycourt at Umag when Djokovic retired in the championship match at 6-6 in the first set.
Djokovic has won three of four meetings since that encounter, including a straight-sets victory in the quarter-finals at Indian Wells earlier this year.
Semi-final results from Rome Masters
3-Novak Djokovic (Serbia) def. Radek Stepanek (Czech Republic) 6-0 1-0 retired (heat exhaustion)
Stanislas Wawrinka (Switzerland) def. 6-Andy Roddick (USA) 3-0 retired (back)