Elina Svitolina required a third-set tie-break to progress at the Indian Wells Open, while former world number one Victoria Azarenka handled an old rival in straight sets and Simona Halep fell victim to an upset. 

Svitolina – the fourth seed – dropped the first set to 32nd seed Sorana Cirstea before fighting back to reach the round of 16 at the WTA Premier 1000 event on Sunday.

Two-time grand-slam champion Azarenka joined Svitolina in the next round after knocking out seventh seed Petra Kvitova, but 11th seed Halep became Aliaksandra Sasnovich's latest conquest. 

SVITOLINA SURVIVES CIRSTEA SCARE

Svitolina needed two hours, 32 minutes to outlast Cirstea 4-6 6-4 7-6 (7-3) and remain unbeaten in three career matches against the Romanian. 

The Ukrainian was on the defensive throughout the opening set, facing 11 break points on her serve and managing to save eight of them before Cirstea finally won out. 

Svitolina tightened things up from there, saving four of five break points the rest of the match. 

"It was a very tough match today, and I was fighting and trying to find my game," said Svitolina, who will face Jessica Pegula next. "It was a bit of a rollercoaster.

"I wish I could play a little bit better in the first set, I had chances to grab that set, but unfortunately it didn't play the way I wanted. I had to fight for every point, and Sorana played a great match, I think. I'm happy that I could win today."

AZARENKA TAKES DOWN KVITOVA

Azarenka won her first two Tour-level matches against Kvitova in 2008 and 2009 but had prevailed only once in six meetings since then before Sunday's 7-5 6-4 triumph. 

The two-time Indian Wells champion converted break-point chances when she needed them, six of 11 in all, and had 18 unforced errors to Kvitova's 26. 

"It was important to just stay there, really take my opportunities, not to let her," Azarenka said after taking down two-time Wimbledon winner Kvitova. "If she gets in the groove in couple points, not to kind of let her extend that streak, if you want to call it that.

"I was trying to still create opportunities for myself, be more aggressive, and honestly just believing also that what I'm doing is right and see how I can execute that. So intention was good. Execution followed after."

ANOTHER UPSET FOR SASNOVICH

After knocking off US Open champion Emma Raducanu in the second round, Sasnovich ushered out another grand slam winner in Halep 7-5 6-4 and will next face Azarenka.

The world number 100 had 22 winners to 16 for Halep and won 61.8 per cent of points on her serve as she reached the round of 16 at Indian Wells for the first time. 

In other matches Sunday, ninth seed Anastasia Pavlyuchenkova fell to 23rd seed and US Open runner-up Leylah Fernandez 5-7 6-3 6-4, while second seed Iga Swiatek dropped only one game in a 6-1 6-0 demolition of Veronika Kudermetova. 

Jelena Ostapenko and Shelby Rogers also advanced. 

Anett Kontaveit ended a four-year title drought by beating Irina-Camelia Begu to win the inaugural Tennis in the Land event on Saturday.

Kontaveit had failed to win a tournament since her maiden WTA Tour triumph in 's-Hertogenbosch back in 2017 before defeating Begu 7-6 (7-5) 6-4.

The world number 30 from Estonia had lost two finals this year, but she was not to be denied in Cleveland.

Begu fought back from 5-2 down in the first set to force a tie-break, but one mini-break was enough for second seed Kontaveit to take a big stride towards an elusive title.

The composed Kontaveit did not face a break point in a tight second set, not allowing her Romanian opponent a look-in as she served superbly.

Kontaveit only had one break-point opportunity of her own, but grasped it to lead 2-1 and went on to seal a confidence-boosting triumph ahead of the US Open.

Sam Stosur will be Kontaveit's opponent in the first round at Flushing Meadows, while Begu faces Andrea Petkovic.

Serena Williams started her quest to match Margaret Court's grand slam record by seeing off Irina-Camelia Begu in the first round of the French Open.

Williams, who reached the semi-finals in Melbourne earlier this year, has been stuck on 23 slam triumphs – one shy of Court's career haul – since winning the 2017 Australian Open.

But the seventh seed in Paris did just enough in a challenging opening outing on Monday, the first official night match in French Open history, overcoming Begu 7-6 (8-6) 6-2 in one hour and 44 minutes.

Begu proved a worthy match, winning four straight games and at one point holding two set points in the opener, but the world number eight's quality and experience ultimately came to the fore.

Having charged into a 5-3 lead, Williams found herself at 0-30 down when serving for the first set, and an overhit slice followed by another errant, awkward backhand gave Begu the break.

More unforced errors followed from Williams as her hopes of clinching the set with a return break were dashed, before the 39-year-old scooped long on her own serve to give Begu the advantage.

The American regained her composure to hit back, though, and force a tiebreak. Begu had two set points to play with at 6-4 up, but Williams rallied, winning the next four to take a hard-fought lead.

A superb drop shot teed Williams up for a break at the start of the second set, yet she tensed up again in game six.

Williams was applauding Begu for a supreme forehand down the line, but the former world number one was soon frustrated as the Romanian clawed back to deuce three times.

Begu's resolve finally crumbled, however, and Williams was left to serve out a win which sets up a second-round tie with Mihaela Buzarnescu.

DATA SLAM: Error-strewn Williams will have to sharpen up

By 3-3 in the tiebreaker, Williams had made 21 unforced errors, in contrast to just seven from Begu. Williams tightened up after nosing ahead, making just nine more in the remainder of the contest, but she will know such issues cannot continue if there is to be a chance of reigning again in the French capital this year.

WINNERS/UNFORCED ERRORS
Williams – 27/30
Begu – 18/17

ACES/DOUBLE FAULTS
Williams – 5/2
Begu – 2/3

BREAK POINTS WON
Williams – 5/8
Begu – 3/5