Angelique Kerber overcame an early scare against Kristina Mladenovic to win her first match as world number one at the Wuhan Open.
Kerber has claimed the Australian Open and US Open titles in 2016 and ascended to the top of the WTA rankings for the first time following her triumph at Flushing Meadows earlier this month.
However, the German appeared in danger of suffering a surprise defeat on Tuesday as her opponent came from 4-2 down to take the opening set in a tie-break.
That proved to be as good as things got for Mladenovic, whose level dropped as Kerber hit her stride and powered to a 6-7 (4-7) 6-1 6-4 victory.
Mladenovic's forehand proved a potent weapon throughout the first set and she moved ahead - at the fourth time of asking - when Kerber produced an error on the same wing trailing 4-6 in the breaker.
Kerber appeared downbeat, yet she was soon displaying the greater consistency, romping through the second set to force a decider.
When Mladenovic, who beat Coco Vandeweghe in round one, was broken to love at the start of set three following successive double faults, the outcome appeared inevitable.
The world number 54 battled hard thereafter, but Kerber proved too strong as she set up a third-round tie with Petra Kvitova.
"I was trying to play more aggressive, to play my tennis. I was moving a bit better [after the first set]," Kerber said on-court.
"It's nice to be here in Wuhan and on centre court with all fans, thank you."