Coco Gauff opens French Open with straight-sets win over Rebecca Marino

American teenager Coco Gauff did not let 10 double-faults, 12 break points or a warning from the chair umpire about receiving coaching from her father disrupt her progress into the second round at Roland Garros.

The 18-year-old Gauff began her trip to Paris with a 7-5, 6-0 victory over Canadian qualifier Rebecca Marino on Sunday. Gauff's best performance at any Grand Slam tournament came a year ago at the French Open, where she reached the quarterfinals before losing to eventual champion Barbora Krejcikova.

Gauff had some serving issues against Marino but managed to set aside 10 of the 12 break points she faced. One key stat that helped Gauff was that she made only 16 unforced errors, while Marino accumulated 40.

Marino was appearing in the French Open for the first time since 2011.

Two-time Grand Slam champion Garbine Muguruza, meanwhile, exited the French Open in the first round for the second year in a row.

Muguruza won the title at Roland Garros in 2016 and was seeded 10th this year but was defeated 2-6, 6-3, 6-4 by Kaia Kanepi of Estonia on Sunday.

Kanepi turns 37 next month and is the oldest player in the women's draw in Paris. She is ranked 46th and is participating in her 15th French Open. Her best showings were quarterfinal appearances in 2008 and 2012; she has appeared in seven Grand Slam quarterfinals but never won one.

The match ended under a drizzle and Muguruza missed a service return on match point, then cracked her racket against the ground.

She beat Serena Williams in the final at Roland Garros six years ago, then defeated Venus Williams in the final at Wimbledon in 2017.

The Associated Press contributed to this report.