Aryna Sabalenka wasted five break points in a dramatic first-set game before finally gaining traction to defeat Brit Katie Boulter 7-5, 7-6 (2), for a place in the third round of the WTA Beijing tournament.
The oddball scheduling for an event which began last week moves the world No. 1 towards the business end of the competition being staged in China after two years of WTA boycott over missing former player Peng Shuai proved futile.
Sabalenka saved eight break points to take a 6-5 lead and concluded the set with a break a game later to win the opener.
Sabalenka did not face any more dramas as she sealed victory with a winning tiebreak in the second set to advance.
The top seed is composting for the first time since taking over the top WTA spot from Iga Swiatek following a finals loss at the US open to Coco Gauff.
Sabalenka improved to 23-0 in the series with Boulter and now plays for the quarter-finals against Italian Jasmine Paolini.
The winner spent two and a half hours in moving through with eight aces and seven double-faults, breaking three times form a dozen chances.
“In the key moments I played a little bit better than her,” Sabalenka said.
“It was all about the last games in each set. I mean, she had the opportunity.
“I’m super happy that I didn’t give her easily those sets. I was keep fighting, keep trying.”