Shahar Pe'er overcame a chest injury and American opponent Meilien Tu to advance to the second round of the US Open late Tuesday night.
The Israeli, who is ranked No. 19 in the world, defeated Tu (45) 6-4, 7-6 (7) despite struggling with injury in recent days.
"I hardly trained in the last five days and had a less than ideal preparation for the match," Pe'er said after her first round encounter. "Luckily, the treatment I received and the break I took helped me. I felt a bit of pain during the warm-up, but wasn't bothered by the injury during the match.
"I'm glad I advanced with relative ease after my poor preparation. I will continue the treatment today and be ready for my next match."
Pe'er will play another American in the second round, after Bethanie Mattek (123) defeated Madison Brengle (217) 6-4, 6-1 in the first round.
Tu was sharper at the start of the match and broke in the second game to open a 2-0 lead. Pe'er broke back immediately and after 30 minutes of play the score was tied at 3-3. The Israeli, who now owns a 5-0 life time record against Tu, claimed her second break in the ninth game and held serve in the subsequent game to close out the set.
Pe'er broke once again in the first game of the second set, but allowed the American back into the match and the second set went to a decisive tiebreak. The Israeli opened a 6-3 lead in the breaker, but Tu reeled off four straight points and reached a set point of her own. The American, however, squandered her chance and three consecutive points for Pe'er completed the victory.
"It took me a while to find my rhythm, but I played very well at the end of the first set," Pe'er said. "I got off to a good start in the second set, but I let her back into the set. We both had our chances in the tiebreak, but I took mine and clinched the match."
Pe'er and Tathiana Garbin, who are seeded 12th in the doubles tournament, played Nadia Petrova and Nicole Vaidisova in the first round late Wednesday night.
Harel Levy, who reached the quarterfinals of the doubles tournament at Wimbledon earlier in the summer, lost with partner Dominik Hrbaty 6-1, 6-4 to Alex Kuznetsov and Jesse Levine in the first round on Tuesday.
French Open mixed doubles champions Andy Ram and Nathalie Dechy faced Maria Kirilenko and Igor Andreev in their first round match late Wednesday.