Top-ranked Novak Djokovic wasted a chance to serve out the match and was beaten 2-6, 7-5, 6-4 by sixth-seeded Tomas Berdych in the Italian Open quarterfinals on Friday.
It's the second consecutive week that Djokovic has struggled, having also lost to Grigor Dimitrov in the second round of the Madrid Open, where he was bothered by a right ankle injury.
Djokovic said he had been playing pain-free this week.
Still, he will need to get his game in shape in a hurry with the French Open starting in less than 10 days on May 26.
Djokovic served for the second set at 5-3 but Berdych ripped a backhand winner that landed on the line on his first break point and won the final four games of the set.