Cori “Coco” Gauff, the 15-year-old American sensation who stunned Venus Williams in her Wimbledon debut, delivered another dominant performance Wednesday, defeating former Wimbledon semifinalist Magdalena Rybarikova in straight sets. Gauff pumped both of her fists after claiming the first match point on Court 1 at the All England Club and advancing to the tournament’s third round.

Gauff, the youngest player to qualify for the main Wimbledon draw, is the first 15-year-old to reach Wimbledon’s third round since 1991. She follows fellow American Jennifer Capriati, who went on to become the youngest person to reach the tournament’s semifinals.

“I’m still shocked I’m even here,” she told the BBC after her win, before later sounding a more confident note.

“I believe I can beat anyone across the court.”

Two days after eliminating Williams, a five-time Wimbledon champion, in the first round of the tournament, Gauff was again measured on the court. She rarely groaned. She appeared confident in handling the powerful serve of Rybarikova, a 30-year-old Slovak. And Gauff remained poised against another established player.

Rybarikova is ranked 139th but was in the top 20 at this time last year. She is a quality grass-court player who reached the Wimbledon semifinals in 2017.

Still, for the second straight match, Gauff was the better player, moving into the third round and earning at least $139,000.

“After she had a huge win like she had in the first round, to come back with that much poise against a woman who got to the semis here two years ago and who is very good on grass, it’s just remarkable,” said the USTA’s general manager of player development, Martin Blackman (via CNN).

Gauff began playing tennis at age 7, inspired by Serena Williams, who said this week that the teenager reminded her physically of a young Venus Williams. All Gauff did Monday was beat one of her idols in straight sets.

“I wouldn’t be here if it wasn’t for her,” Gauff said after beating Venus Williams. “And I was just telling her that she’s so inspiring. Like, I always wanted to tell her that. And even though I met her before, I guess now I have the guts to.”

Earlier Wednesday, eight-time Wimbledon champion Roger Federer walked by Gauff. “There she is!” he said. “How’s everything? Congratulations. Great job.”

“Play well,” he said as he walked away.

Gauff said this week she had spoken with Federer via telephone after losing a match earlier in her young professional career.

Gauff was coached early in her career by her father, Corey, who played basketball at Georgia State. Her mother, Candi, was a hurdler and heptathlete at Florida State. Both were in attendance Wednesday.

Gauff will face Polona Hercog, 28, in the third round Friday.

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