And that was understandable.
After all, the 17-time Grand Slam winner was playing for the first time since the birth of his second set of twins last week.
“This one is totally OK if it doesn’t hurt,” Federer said. “I tried everything. I can’t do more than that on the court.”
“That passing shot is a tough one for me to take, because he’s not going to make that very often,” Federer said. “But it happens and credit to him to fight his way back into the match and get it.”
Later, top-ranked Rafael Nadal also faced stiff resistance from his French opponent before ultimately wearing down 30th-ranked Gilles Simon for a 7-6 (1), 6-7 (4), 6-2 win that lasted 3 hours, 18 minutes - opening his bid for an eighth Rome title.
Nadal hit 32 winners but just three with his backhand, which has become a point of concern recently.
Also, Wimbledon champion Andy Murray eliminated Marcel Granollers of Spain 6-2, 7-5.
Women’s title-holder Serena Williams showed no problems - and no taping - from a left thigh injury that forced her to withdraw from Madrid. The top-ranked American beat 28th-ranked Andrea Petkovic 6-2, 6-2.
“I’m not 100 percent but I’m getting there,” Williams said, adding that the conditions at the U.S. Open prepared her for the heavy wind gusts at the Foro Italico. “If I can play in New York, I can play anywhere.”
Maria Sharapova, the 2011 and 2012 Rome champion, had to rally in the second set to get by Puerto Rican qualifier Monica Puig 6-3, 7-5.