NEW YORK  —Greek tennis player Maria Sakkari has risen to number 13 in the world, a record WTA ranking for Greek women's tennis, after defeating number four seed Karolina Pliskova in two straight sets to reach the semi-finals in the US Open.

In an impressive game on Wednesday, Sakkari showed command of the court and her powerful serve secured a win against her opponent, who was runner-up in Wimbledon. This will catapult her five positions higher than her current ranking, number 18, which was also a personal record, and bring her one position higher than the previous best ranking achieved by a Greek woman player, when Lena Daniilidou had ranked 14th in the WTA rankings for six weeks in 2003.

If Sakkari prevails against her opponent Emma Raducanu on Friday and reaches the finals, she will be one of the WTA top 10 for the first time, while if she wins the tournament she will be have made an impressive leap of 14 positions to rank 4th worldwide.

Raducanu, 18, 1st qualifier in US Open semis; Sakkari next

When Emma Raducanu got to Flushing Meadows to try to win her way through qualifying and earn what would be a berth in her second Grand Slam tournament, she was not planning on a particularly long stay.

Look at her now, two weeks into this adventure: The 18-year-old from Britain is the first qualifier in the professional era to reach the U.S. Open semifinals. And she hasn't even dropped a set yet.

“My flights were booked at the end of qualifying,” Raducanu said with a chuckle Wednesday, “so it’s a nice problem to have."

Showing off the shots and poise of someone much more experienced, the 150th-ranked Raducanu became the second unseeded teen in two days to secure a spot in the final four, eliminating Tokyo Olympics gold medalist Belinda Bencic 6-3, 6-4 in Arthur Ashe Stadium.

Not bad for someone ranked outside the top 350 in June after going about 1 1/2 years without a match — in part because of the coronavirus pandemic, in part because her parents wanted her to finish high school.

“I’m not here to chase any records right now,” said Raducanu, only the third woman not ranked in the top 100 to make it this far at the U.S. Open and only the fourth qualifier to advance to the semifinals at any major tournament since the Open era began in 1968. “I’m just taking care of what I can do (in) the moment.”

Raducanu has won all 16 sets she has contested through eight matches in New York — three during the qualifying rounds and another five in the main draw. On Thursday, she will face No. 17 seed Maria Sakkari of Greece, a semifinalist at this year’s French Open.

Sakkari won 22 consecutive points she served in one stretch and beat No. 4 Karolina Pliskova, a two-time major runner-up, 6-4, 6-4 on Wednesday night to follow up her victory over 2019 U.S. Open champion Bianca Andreescu in the previous round.

“I'm impressed,” Sakkari said with a smile during her on-court interview when she was informed of that serving streak. “I trusted my serve, but now I'm going to trust it even more.”

The other women's semifinal will be 19-year-old Leylah Fernandez of Canada against No. 2 seed Aryna Sabalenka of Belarus.

In the men's quarterfinals Wednesday, Olympic champion and 2020 U.S. Open runner-up Alexander Zverev stretched his winning streak to 16 matches with a 7-6 (6), 6-3, 6-4 victory over unseeded Lloyd Harris.

Harris went up 5-3 in the opening set but got broken while serving for it. He then held a set point at 6-5 in the tiebreaker but couldn't convert, and the fourth-seeded Zverev was on his way. The 24-year-old from Germany grabbed the next three points for that set, then moved out to leads of 3-0 in the second and 4-0 in the third.

“Somehow managed to win that first set,” Zverev said. “Loosened me up a little bit.”

Shortly after he lost to Dominic Thiem in last year's final at Flushing Meadows, Zverev was accused by a former girlfriend of domestic abuse, allegations he repeatedly has denied.

His second consecutive U.S. Open semifinal will come against No. 1 Novak Djokovic, who is bidding for the first calendar-year Grand Slam by a man since Rod Laver in 1969 and moved two wins away by defeating No. 6 Matteo Berrettini 5-7, 6-2, 6-2, 6-3 in the quarterfinals.

Raducanu made her Grand Slam debut at Wimbledon thanks to a wild-card invitation and she made it to the fourth round before stopping during that match when she had trouble breathing.

That tournament allowed the world to begin to get familiar with her style of crisp, clean tennis, managing to attack early in points from the baseline without sacrificing accuracy. By the end against the 11th-seeded Bencic, a U.S. Open semifinalist in 2019, Raducanu had nearly twice as many winners as unforced errors, 23-12.

She also showed gumption, both at the beginning, when she was undaunted by a 3-1 deficit and claimed the next five games, and at the end, when she fell behind love-30 each of the last two times she served before hanging on.

“Obviously, she’s very solid,” said Bencic, who hadn't dropped a set in the tournament before Wednesday, “to just kind of stay tough till the end and just play her game and kind of not let me in again.”

When Bencic double-faulted to get broken and fall behind 3-2 in the second set, she trudged, slow as can be, to a corner of the court to retrieve her towel. When she got to her sideline seat, she whacked her racket against her equipment bag, then plopped herself down and smacked the racket against the ground.

Raducanu jogged to the sideline, showered in applause and cheers from the crowd.

Just like the prior afternoon, the Ashe spectators lent their considerable support to a teenager whose name is not yet well-known and who's not yet all that accustomed to gracing these stages.

On Tuesday, a day after turning 19 and sharing cupcakes with Raducanu and others in the locker room, it was Fernandez getting past No. 5 seed Elina Svitolina 6-3, 3-6, 7-6 (5) to become the youngest semifinalist at Flushing Meadows since Maria Sharapova in 2005.

On Wednesday, it was the even-younger Raducanu's turn.

Her father is Romanian, her mother is Chinese, and Raducanu was born in Toronto, before the family moved to England when Emma was 2.

Mom and Dad did not make the trip to New York — and they’re not exactly in constant contact with their precocious daughter.

“I haven’t actually called my parents for quite a while,” Raducanu said with a sheepish smile and a roll of her eyes. “Yesterday, like the day before, they were ghosting me.”