PARIS (AP) — The Latest from the French Open (all times local):
Last year's runner-up Marketa Vondrousova lost in the first round of the French Open.
The 15th-seeded Czech player was beaten by Iga Swiatek 6-1, 6-2.
Vondrousova was the third-lowest ranked player to reach the final last year when she did so at No. 38.
Swiatek reached the fourth round at Roland Garros last year. The 19-year-old Polish player will next face Hsieh Su-wei of Taiwan.
Serena Williams advanced to the second round of the French Open by beating Kristie Ahn 7-6 (2), 6-0.
The sixth-seeded Williams served for the match at 40-0 but Ahn saved three match points. An ace gave her a fourth opportunity to win but she hit a shot into the net.
Williams then saved a break point before finally beating her American opponent with an ace.
Ahn held leads of 3-1 and 4-2 in the first set.
The 39-year-old Williams is a three-time French Open champion and is looking to equal Margaret Court's record of 24 major titles. She will next face Bulgarian wild-card entry Tsvetana Pironkova.
Fourteenth-seeded Fabio Fognini and 19th-seeded Felix Auger-Aliassime both lost in the first round of the French Open.
Fognini lost to Mikhail Kukushkin 7-5, 3-6, 7-6 (1), 6-0 and Auger-Aliassime was beaten by Yoshihito Nishioka 7-5, 6-3, 6-3.
It was the 20-year-old Auger-Aliassime's first main-draw appearance at Roland Garros.
Fognini reached the French Open quarterfinals in 2011 for his best performance at a major tournament. This was his earliest exit at Roland Garros since a first-round loss in 2016.
U.S. Open champion Dominic Thiem advanced to the second round of the French Open by beating former U.S. Open champion Marin Cilic 6-4, 6-3, 6-3.
The third-seeded Austrian won his first major tournament at Flushing Meadows two weeks ago and is among the favorites again at Roland Garros after losing the past two finals to Rafael Nadal.
Thiem broke the imposing Croatian's serve six times in cool conditions on Court Philippe Chatrier.
Cilic led 2-0 in the third set but Thiem reeled off the next five games before Cilic held again.
Thiem will next face American qualifier Jack Sock. He beat Reilly Opelka 6-4, 6-4, 6-3.
Petra Kvitova reached to the second round of the French Open after a 6-3, 7-5 win over Oceane Dodin under the new roof on Court Philippe Chatrier.
The two-time Wimbledon champion advanced from the first round for the 10th time in 11 appearances at Roland Garros. The Czech player's only first-round loss was in 2010. She was a semifinalist in 2012. She is ranked 11th and seeded seventh at Roland Garros.
A forehand hit wide by 118th-ranked Dodin gave Kvitova a break of serve in the second set. The 23-year-old Frenchwoman was playing the 30-year-old Kvitova for the first time.
The new roof over Court Philippe Chatrier is again proving its worth on Day 2 of the French Open.
The court is hosting the only play as rain thwarted the start of all other matches at Roland Garros. Two-time Wimbledon champion Petra Kvitova and 118th-ranked Oceane Dodin were dry for their first-round match with Chatrier’s retractable roof deployed from the outset.
No other matches started as scheduled on 12 other courts with rain falling and forecasters predicting dryer weather for the afternoon. Waterproof covers were deployed on all those courts to keep them from getting soaked.
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