Serena Williams Moves Closer to Grand Slam History With US Open Quarterfinal Win

— -- Serena Williams fought off losing her first set in this year’s U.S. Open on Wednesday night to beat No. 5 seed Simona Halep and earn a berth in the semifinal.

The 6-2, 4-6, 6-3 quarterfinal win gave No. 1 seed Williams, 34, her 309th Grand Slam match win and put her one step closer to winning her 23rd career major title.

Taking the women’s title this week would put Williams ahead of Steffi Graf for the most singles championships since the introduction of the open era in 1968, when the Grand Slam tournaments agreed to permit professional players to compete with amateurs.

A U.S. Open win by Williams would also move her ahead of Chris Evert for the most U.S. Open singles titles, at seven.

“I’ve never met anybody like her before,” Evert, who retired in 1989, told ABC News Wednesday just before Williams’ quarterfinal match. “She wants to be the greatest at everything that she does.

“She’s sort of got that insatiable appetite to excel, and that’s why she’s a tennis champion,” Evert said. “She’s a perfectionist.”

Evert reflected on her own groundbreaking career, including 18 Grand Slam singles crowns, at an event Wednesday for American Express Starwood preferred guest credit card members.

She now coaches players at the Chris Evert Tennis Academy in her home state of Florida and said her relationship with Williams, who also trains in South Florida, is as a friend, not a mentor or coach.

“We keep in touch a lot, and I try to encourage her, because I believe in her,” Evert said. “As far as a mentor, she had that in her mom and dad and her older sister Venus.”

Williams will face Karolina Plishkova, 24, in the semifinals tonight. Plishkova, the No. 10 seed, defeated Venus Williams in three sets in the fourth round.

The Serena Williams–Plishkova match is being hyped as one that could see a record number of aces, given the two players’ serve domination. Evert, an ESPN commentator, said she watches for two things at the start of Williams’ matches to see whether she is on her game.

“I watch her moving right from the start, to see if she’s moving well. That’s a sign of nerves if she’s stuck and not moving well,” Evert said. “And her first serve. She needs those two things to win.”

Williams will turn 35 later this month, and Evert said she sees no signs of the tennis legend slowing down.

“Serena, she has passion in her,” Evert said. “She’s very intense, and she still wants it.”