Serena Williams felt below her best, despite reaching the third round of the French Open on Thursday.
The eighth-seeded American beat Milagros Sequera of Venezuela 6-0, 7-6 (3), keeping alive her chances of winning a second straight Grand Slam.
"It was weird," said Williams, who won the Australian Open in January. "I didn't feel like I played my best tennis throughout the whole match. I was kind of struggling out there to get the rhythm."
Williams felt uneasy on center court - even after sweeping the first set.
"I honestly didn't feel my game at all today," Williams said. "I was just kind of a little bit everywhere today."
Williams was trailing 3-0 in the second set but rallied back, and clinched victory on her first match point.
Sequera hit one drop shot toward the end of the second set that even Williams applauded.
"A feisty young player, and a motivated player," Williams said of Sequera. "It was definitely a tough match."
Williams, an eight-time Grand Slam champion won the French Open in 2002, had not played at Roland Garros since reaching the quarterfinals in 2004.
The former top-ranked Williams, next plays Michaella Krajicek of the Netherlands, has won two titles this year.