Jelena Ostapenko, Jil Teichmann and Dayana Yastremska dealt out a trio of upsets on Day 3 of the Dubai Duty Free Tennis Championships. Ostapenko triumphed in an extraordinary battle over No.6 seed Iga Swiatek 4-6, 6-1, 7-6(4), Teichmann took out No.10 seed Elina Svitolina 7-6(0), 6-2 and Yastremska ousted No.2 seed Barbora Krejcikova 6-3, 7-6(3).

It is the third win over Swiatek in as many meetings for Ostapenko, who also defeated the Pole at Birmingham 2019 and Indian Wells 2021. But this wildly oscillating contest, which featured 16 breaks of serve and remained unpredictable until the last ball, was the first time that the two former Roland Garros champions had gone three sets with each other.

The result marks the first time that Ostapenko has won consecutive main draw matches in Dubai. Fresh off the St. Petersburg semifinals last week, the Latvian will bid for a second straight last-four run against either No.1 seed Aryna Sabalenka or 2013 champion Petra Kvitova.

Keys to the match: Both players struggled to hold serve, particularly in a first set that saw six consecutive breaks. This was partly down to a no-holds-barred approach on return - both Ostapenko and Swiatek relished every chance they had to swat a clean return winner - but Ostapenko was also beset by nine double faults across the match.

The reliability and efficacy of the 24-year-old's serve has been key to her quietly resurgent form since winning Eastbourne last July, and this was a significant dip in its level. However, Ostapenko impressed by maintaining her composure and accuracy despite this, and throughout severe scoreboard pressure at times.

Scoreboard management: During the sequence of first-set service breaks, it was Ostapenko chasing Swiatek from behind - and though she caught up to level at 4-4, her backhand and dropshot both went awry when serving to stay in the set.

Nonetheless, the World No.21 shook off the disappointment to race through nine of the next 10 games, coming out on top of almost every 30-30 or deuce moment to build a 3-0 third-set lead and hold a point for 4-0. But closing it out from there required surviving several more momentum shifts as Swiatek clung on.

The 20-year-old avoided the double break thanks to a service winner, and managed to level at 3-3. But Ostapenko regained her advantage after coming through a gripping eight-deuce tussle to break Swiatek for 5-3. In that game, Ostapenko smacked three return winners on deuce points and converted her seventh break point with a fizzing forehand down the line.

But Ostapenko was unable to serve out the win, double faulting down break point, and she missed a match point in the subsequent game with a long backhand. For the first time, she seemed to lose her cool, conceding her own serve in a flurry of errors to fall behind 6-5.

However, Ostapenko regained control impressively quickly. Two more return winners settled her again, and prevented Swiatek from serving out the match. In the subsequent tiebreak, it was Swiatek's forehand that repeatedly broke down, and Ostapenko moved through on her third match point.

Teichmann upsets Svitolina for second straight encounter

Teichmann, who reached her first WTA 1000 semifinal in Dubai last year, is only competing in this year's draw as a lucky loser after falling to Katerina Siniakova in the last round of qualifying.

But the Swiss player has made the most of her second chance, reaching her first quarterfinal of 2022 with her second straight win over Svitolina. In one of the finest matches of last year, Teichmann saved six match points en route to a 2-6, 6-4, 7-6(5) triumph in the first round of Madrid, and she reprised that upset here in 1 hour and 42 minutes.

Highlights: Teichmann d. Svitolina

Teichmann's first serve was the lynchpin of her victory. She conceded only seven points behind it, two in the first set and five in the second, and it helped her stave off each of the five break points she faced (all in the second set). It was ably backed up by the World No.35's swashbuckling left-handed forehand, which garnered her 16 total winners.

Svitolina, who captured the Dubai title in 2017 and 2018, delivered solid serving numbers of her own to take the first set to a tiebreak - but Teichmann punished the Ukrainian's passivity off the ground to win it with a whitewash.

A tactical switch-up from Svitolina seemed promising at the start of the second set, with the former World No.3 striking out on her backhand and finishing points at net. But in the most absorbing passage of play, Teichmann responded by raising her level and gritting out four multi-deuce tussles in a row. She will next take on Veronika Kudermetova, who upset defending champion Garbiñe Muguruza, for a semifinal spot.

Yastremska scores third Top 5 win over Krejcikova

Former World No.21 Yastremska's return to action last July after being exonerated of an anti-doping violation started promisingly with a run to the Hamburg semifinals. But between that tournament and Dubai this week, the Ukrainian managed to win just five of 14 matches. Victories over Anna Danilina, Clara Tauson and Madison Brengle in qualifying kickstarted her tally of 2022 victories, but her defeat of Krejcikova is Yastremska's first Top 5 win since beating Sofia Kenin at Doha 2020, and her third overall.

Like Teichmann, a rock-solid serving performance underpinned Yastremska's success. Landing 72% of her first deliveries and winning 76% of those points, she built a lead of a set and a break without facing a break point. Picking her moments to attack a somewhat flat Krejcikova, aggressive returning had seen the 21-year-old break her opponent once in each set.

Highlights: Yastremska d. Krejcikova

As No.146-ranked Yastremska reached the verge of victory, things got more complicated. She seemed to have staved off a potential turning point after saving four break points to hold for 5-3, sealing the game with a bold backhand winner. But edgy errors were creeping into her game, and Krejcikova took full advantage to level at 5-5.

The Czech was beginning to raise her game, but Yastremska gathered herself impressively. Serving down 5-6, she found her best tennis of the day to force and then dominate the tiebreak.

Yastremska will next face either Marketa Vondrousova or fellow qualifier Varvara Gracheva as she bids for her first WTA 500 semifinal since Adelaide 2020.