SINGAPORE - No.5 seed Venus Williams scored her first win of the BNP Paribas WTA Finals Singapore presented by SC Global in commanding fashion, defeating French Open champion Jelena Ostapenko in three close sets.

Venus needed over three hours to win the longest match of the 2017 WTA Finals and overcome Ostapenko’s determined challenge 7-5, 6-7(3), 7-5, improving to 1-1 in the White Group.

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“A win is a win, that's all I can say,” Venus told reporters in her post-match press conference. “Maybe I got a little luck. Who knows? But I'm on to the next match now.”

And clocking in at exactly 193 minutes, Venus’ victory over Ostapenko is officially the third-longest WTA Finals match since 2008, when match stats were first recorded. The record for longest WTA Finals match was set in 2012 when Agnieszka Radwanska needed 209 minutes to defeat Sara Errani in Istanbul.

Venus edged in front after a roller coaster opening set, which set the tone for the tortuous match to follow. The American rallied back from 3-5 down and won the next four games to steal the set from Ostapenko, who flubbed a couple of backhands to go give Venus the lead.

In the second, Venus had multiple chances to close out Ostapenko - even holding a match point at 6-5 on the Latvian’s serve - but she was denied time and time again. Just as Venus started to get tight, firing two double faults in the tiebreaker and mishitting a slew of errors, Ostapenko roared back to life to take the match the distance.

Ostapenko started off the third by denying Venus five break point chances, but that pattern didn’t last for long. Six straight breaks of serve sent the momentum seesawing between the two players, neither able to hang onto the lead for long and leaving them level at 4-4.

The Latvian’s serve was increasingly vulnerable as the match ticked towards the three-hour mark, and Venus kept her under pressure. She finally grabbed the decisive break late in the match to close out her first win of the tournament.

The American hit 26 winners and 29 unforced errors and withstood a barrage of 48 winners from Ostapenko, who also struck 40 unforced errors. The serve proved to be the key for both players; while Venus first serve was at 61%, Ostapenko's dipped to 46% in the third set, allowing Venus to create and convert more break points (11 of 26 against Ostapenko's 9 of 18). 

“I was just a little bit tight in some moments,” Ostapenko reflected in press. “When I had to serve, I didn't really serve.

“[Venus] was playing good today. She was serving well. It was hard to break her, but I think I was returning pretty well today, better than serving. We had a very long match and some good rallies.”

Up next on Thursday, Venus will take on Garbine Muguruza and Ostapenko will face Karolina Pliskova in the last matches of White Group action.

Both Venus and Ostapenko are still alive in the White Group, and while both players face an uphill climb to reach the knockout stage, the road is now much tougher for Ostapenko, who goes down to 0-2. Venus improves to 1-1, and depending on other results, could battle for the White Group No.2 spot on Thursday.