PARIS (AP) - The Latest on the French Open (all times local):

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11:35 a.m.

French Open organizers say American player Sam Querrey has withdrawn from the clay-court Grand Slam tournament.

Querrey, who was set to take on Spanish qualifier Pedro Martinez in the first round, has been replaced in the main draw by lucky loser Henri Laaksonen of Switzerland.

A Wimbledon semifinalist in 2017, the 62nd-ranked Querrey cited an abdominal problem as the reason for his withdrawal.

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11:15 a.m.

The year's second Grand Slam is underway.

Under sunny skies, former No. 1 Angelique Kerber lost the first two games to 81st-ranked Anastasia Potapova in the opening match on Court Philippe Chatrier.

The French Open is the only Grand Slam tournament that Kerber has never won.

On Court Suzanne Lenglen, 11th-seeded Marin Cilic is facing Thomas Fabbiano.

Also, 2016 champion Garbine Muguruza is up against 96th-ranked American Taylor Townsend in the first match at the tournament's newest stadium, Court Simonne Mathieu.

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8:45 a.m.

Roger Federer is in action on the opening day of the French Open.

Returning to play at Roland Garros for the first time since 2015, Federer opens against 73rd-ranked Lorenzo Sonego in the third match on Court Philippe Chatrier.

Also Sunday, 2016 champion Garbine Muguruza faces 96th-ranked American Taylor Townsend in the first match at the tournament's newest stadium, Court Simonne Mathieu.

Sixth-seeded Stefanos Tsitsipas, who beat Federer at the Australian Open, plays Maximilian Marterer.

Others in action include: seventh-seeded Kei Nishikori; last year's semifinalist Marc Cecchinato; last week's Italian Open champion Karolina Pliskova, Venus Williams and Sloane Stephens.

The French Open is the only one of the four Grand Slam tournaments to begin on a Sunday.

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