PARIS -- Qualifier Lauren Davis, an 18-year-old from Boca Raton, Fla., knocked off 30th-seeded Mona Barthel of Germany 6-1, 6-1 in the first round of the French Open on Monday.

It was Davis' first victory in three career Grand Slam matches.

She played cleanly, making only 11 unforced errors. Barthel made 44, including 12 double-faults.

The 5-foot-2 Davis finished last season ranked 319th, and she entered this week 162nd.

Also on HuffPost: