PARIS (AP) Andy Murray benefited from a double-fault by Juan Martin del Potro in the opening tiebreaker and then looked more and more like the No. 1 player that he is during a 7-6 (8), 7-5, 6-0 victory at the French Open on Saturday.
The third-round match between a pair of past major champions was much tighter than the straight-set scoreline might indicate.
''Yeah, I expected a very tough match. And the first set was very, very important, I think, for the rest of the match. Whoever had won that first set had big momentum,'' Murray said. ''In these conditions, when it's slow and heavy, to be coming back is difficult.''
He needed nearly 3 hours to get past the 29th-seeded del Potro at Court Philippe Chatrier under a cloud-filled sky. It was a rematch of the 2016 Rio Olympics gold-medal final won by Murray.
Del Potro had four set points in the opening set but lost each one, including that key double-fault while ahead 7-6 in the tiebreaker. After Murray converted a third set point of his own when his opponent's big forehand landed barely wide, del Potro rested his head on the net and stayed put for several seconds, the very picture of disappointment.
''Too much frustration,'' del Potro said. ''I couldn't believe I lost that set.''
Murray is a three-time Grand Slam title winner and was the runner-up at Roland Garros a year ago. He has not had a great season so far, though, particularly on the clay-court circuit leading up to the French Open, but he now has reached the fourth round for the eighth time in 10 appearances in Paris.
''I'm starting to feel better. I was really looking forward to the French Open,'' Murray said. ''I had struggled the last six or seven weeks coming in.''
Del Potro, the 2009 U.S. Open champion, was playing at his first French Open since 2012 because of a series of operations on his left wrist. Under constant pressure from an aggressive foe, del Potro had some trouble from Murray's drop shots and wound up making far more unforced errors, 43-28.
Also on Day 7, 2014 U.S. Open champion Marin Cilic beat Feliciano Lopez 6-1, 6-3, 6-3, and next meets big-serving Kevin Anderson, who edged Kyle Edmund 6-7 (6), 7-6 (4), 5-7, 6-1, 6-4. Fernando Verdasco easily got past No. 22 Pablo Cuevas 6-2, 6-1, 6-3.
Victories by Alize Cornet and Caroline Garcia gave France three women in the fourth round of this tournament for the first time since 1994. Kristina Mladenovic advanced to that round by winning Friday.
The unseeded Cornet was a surprisingly easy winner against No. 9 Agnieszka Radwanska of Poland, 6-2, 6-1, while No. 28 Garcia edged Hsieh Su-wei of Taiwan 6-4, 4-6, 9-7.
France, which last put a trio of women into the final 16 at any major at the 2008 U.S. Open, is guaranteed at least one quarterfinalist this time, because Garcia now meets Cornet.
''I think the crowd is going to be excited,'' Cornet said. ''We will try to give them a good show, a good game. The crowd support is like a bonus, an extra energy.''
Simona Halep, the 2014 runner-up, said the torn ligament in her right ankle is no longer an issue and proved that by defeating 26th-seeded Daria Kasatkina of Russia 6-0, 7-5.
''Well, now, it's pretty OK,'' Halep said about her ankle. ''I can run. I can slide everywhere. I can move pretty well.''
In other third-round action, former No. 1 Caroline Wozniacki beat 18-year-old CiCi Bellis of California 6-2, 2-6, 6-3 in a match suspended late in the second set Friday night; and No. 21 Carla Suarez Navarro eliminated No. 14 Elena Vesnina 6-4, 6-4.
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