Aryna Sabalenka fought from a set behind to come back and defeat Ons Jabeur 3-6 7-6 (7-5) 7-5 in their first match of the WTA Finals on Monday.
Sabalenka, 24, has now won her past three matches against Jabeur, and this time around it was her ability to limit the effectiveness of the Tunisian's serve that turned the tide.
Jabeur's serve dominated the opening set, winning 73 per cent (16-of-22) of her service points while not allowing Sabalenka a single break point opportunity.
The second set was a different story, as some double faults crept into Jabeur's game and her success rate on her service points dipped to 51 per cent (24-of-47), allowing Sabalenka to break three times before forcing a decider with a close tiebreaker.
Sabalenka finally got on top in the third set, narrowly edging the total points count 37 to 31 in the frame while converting both of her break point chances to finish off the victory.
She now sits second in the Group B standings, trailing Maria Sakkari due to the Greek winning her match in straight sets.
BREAK POINTS WON
Sabalenka - 5/8
Jabeur - 6/10
Sabalenka - 21/26
Jabeur - 37/29
Sabalenka - 1/6
Jabeur - 7/5