Hong Kong - Seven-time Grand Slam winner Venus Williams battled through a gruelling first-round match at the Hong Kong Open Tuesday, taking three sets to beat unseeded Yuliya Beygelzimer.
The American finally sealed victory 2-6, 6-4, 6-4 after more than two hours on court.
Williams, 35, is fighting for a place in the eight-player WTA Finals in Singapore later this month with Hong Kong her last chance to get the points she needs.
She is currently 11th in the Road to Singapore rankings.
Williams has had a resurgent season, winning her biggest title in five years in Wuhan at the beginning of October.
But Ukrainian Beygelzimer, who came into the competition as a last-minute Lucky Loser from the qualifying rounds, outpaced her in the first set with blistering returns.
Williams hobbled around the court with a strapped left thigh but managed to claw her way back to one set all.
Both players dropped their serve in the third, but Williams finally turned on the power to take the set with a scorching pass.
Former world number one Jelena Jankovic also struggled to find her rhythm against Romanian qualifier Ana Bogdan but went on to seal a 6-4 6-2 win.
Australia's Samantha Stosur and Caroline Garcia of France went through to the second round, as did Britain's Heather Watson.
World number 10 Angelique Kerber takes on former French Open winner Francesca Schiavone in the final match of the day.