Coco Gauff confirmed her semi-final spot at the WTA Finals with a rare win over defending champion Iga Swiatek.
The American beat second seed Swiatek 6-3 6-4 to join Aryna Sabalenka in the last four in Riyadh, Saudi Arabia.
The result also means Sabalenka will be the year-end world number one as number two Swiatek can no longer catch her in the rankings.
It is only the second time Gauff has defeated Poland’s Swiatek in 13 attempts.
“It feels great,” said 20-year-old Gauff. “I knew going into the match, despite our head-to-head, I had a lot of confidence and I felt like I was playing great tennis.
“Even when I was playing a little bit sloppy, the games that I lost were still going to deuce. That gave me confidence and I knew if I stayed solid I had the chance to close out the match.”
Earlier, Gauff’s compatriot Jessica Pegula became the second player to be eliminated from the season-ending tournament – after Elena Rybakina on Monday – following her 6-3 6-3 defeat by Barbora Krejcikova.
Swiatek must beat Pegula in Thursday’s final Orange Group match to progress, while third seed Gauff has to hold off Czech Krejcikova in order to top the group standings.
Not since last year’s Cincinnati Open had Gauff beaten 23-year-old Swiatek, on that occasion in three sets, and the American piled the pressure on her opponent from the start of their meeting in Riyadh.
French Open champion Swiatek – playing only her second match under new coach Wim Fissette – saved four break points early in the first set before her backhand over the baseline put Gauff ahead at the fifth opportunity.
Gauff then converted set point on Swiatek’s serve as the Pole hit a wayward forehand out of bounds.
But Gauff’s game fell apart at the start of the second set, forced into saving five break points across her opening two service games – in which she also made six double faults – before Swiatek finally got one over the line.
But she immediately broke back to love as she regained her composure, then holding again from break point down.
The pair traded more breaks in a topsy-turvy set, in which seven of the first eight opening games featured break points.
Gauff’s first love-hold of the match followed, before Swiatek handed her the win with a long forehand return on match point.
Pegula eliminated after lacklustre performance
Image source: Reuters
Image caption: At last year’s WTA Finals, Jessica Pegula lost to Iga Swiatek in the final
In Tuesday’s earlier match, Wimbledon champion Krejcikova faced little challenge from a below-par Pegula, who last year reached the tournament’s final.
In a performance devoid of any positive energy, Pegula struggled to cope with the Czech’s huge serves, including 11 aces, and hit just four winners in a match lasting little more than an hour.
US Open finalist Pegula, 30, had got off to the perfect start with a love hold in her first service game, amid a catalogue of Krejcikova unforced errors.
But after Krejcikova got the initial break midway through the first set, sixth seed Pegula’s body language began to sour and she gifted her opponent the opener with a sloppy return tapped into the net from close range.
Form did not improve for Pegula at the start of the second set as Krejcikova broke her serve at the first opportunity, though there was a brief reprieve for the American as she cancelled that out in the next game.
But any glimmer of hope for a Pegula comeback was extinguished as she double-faulted to give her opponent the break back, after which Krejcikova – whose performance was far from polished – coasted to a straightforward victory with a solitary break point her only hurdle.
“I’m really pleased with the way I played today. I felt I had to play my best tennis,” said eighth seed Krejcikova, who is ranked 13th in the world but qualified for the WTA Finals on account of being a 2024 Grand Slam champion.
“I had some very high parts of the season, especially winning the Wimbledon title. It was something that is really indescribable, and to be here right now is a huge privilege to be playing in the final eight.”
The WTA Finals are being held in Saudi Arabia for the first time – a move which has been criticised by some because of the country’s human rights record.
This year’s tournament has record prize money, with the singles champion set to collect about £4m.
In Wednesday’s final Purple Group round-robin matches, Sabalenka will take on Rybakina before Jasmine Paolini and Zheng Qinwen go head-to-head for a place in the semi-finals.