Anastasia Potapova, 18, makes debut at French Open by ousting 3-time Grand Slam champ Angelique Kerber

Angelique Kerber’s quest to complete a career Grand Slam this year was squashed during the first round of the French Open at the racket of an 18-year-old making her debut.

Russian Anastasia Potapova defeated the fifth-seeded German, 6-4, 6-2, in 73 minutes. It was her first time at Roland Garros and her second career match against a player ranked in the top 10. Potapova is ranked 81st in the world.

Kerber’s loss impacted by ankle injury

Kerber came into the French Open nursing a right ankle injury she suffered at the Madrid Open. She “did not have much expectation” after pulling out of the Madrid and Rome clay tournaments heading into Paris.

Kerber said, via The Associated Press:

"Of course this is not my excuse and everything. I tried my best. I know that there is still a little bit of work to do to be really playing matches 100 percent."

Kerber, 31, is a formerly No. 1-ranked player who won the Australian Open and US Open in 2016. She added a Wimbledon title in 2018 and is now chasing a title at Roland Garros to have the career Grand Slam, though it’ll now wait at least another full year.

She told the AP she was happy her clay season was over and she “can now look forward to playing on grass.” It was only her third match on clay this season. She told the BBC:

"I was able to practice in the last few days really good, but it was not a long clay-court preparation with everything. At the end, I was just happy to at least go on court, playing a match, and of course it is not like I hoped for."

She’s made it only as far as the quarterfinals at Roland Garros, a feat she matched last year. Kerber has lost in the first round six of her 12 appearances there, including in three of the past four years.

Potapova makes stunning debut

Potapova showed nerves early, but calmed and finished off her first victory over a top-10 opponent. The 18-year-old won the opening set when Kerber blew a 40-0 lead at 5-4. She powered to a 4-0 lead in the second set.

She faces either China's Wang Yafan or Czech Marketa Vondrousova of the Czech Republic in the next round.

Potapova is a former junior world No. 1 who won the junior Wimbledon title. She started her first year on tour in 2017 and saw some success the following year.

More from Yahoo Sports:

• Giannis leaves Game 6 postgame presser mid-question

• Kawhi leads Raps to first-ever NBA Finals

• Rockets clean house with D'Antoni's coaching staff

• Rays, Yanks bracing for bidding war over Keuchel, Kimbrel