Venus Williams' first visit to Asia since 2017 was cut short as she crashed out of the Wuhan Open first round on Sunday 7-5, 7-6(5) to fellow American Danielle Collins.
The 39-year-old Williams, a 2015 Wuhan champion now 59th in the world rankings, squandered a lead in the first set before eventually losing to Collins, who recorded just the second match win of her career on Chinese soil.
The 35th-ranked Collins rallied back from 3-5 down in the opening set, winning a whopping nine games in a row to go up 7-5, 5-0.
Williams, a wildcard at Wuhan this year, finally stopped the bleeding, holding the serve to interrupt her opponent's momentum.
It was the start of a surprising five-game run from Williams, who saved two match points along the way as she drew level at 5-5.
In the decider, Williams got the first mini-break but it was Collins who eventually created a 6-4 gap, converting with an ace on her fourth match point to move into the second round.
It was Collins' second triumph over Williams, who had also stumbled against the 25-year-old during the Miami Open last year.
"This is my first tournament here in Asia, I was just happy to come out with a win, said Collins, who next takes on defending champion and ninth seed Aryna Sabalenka, a 6-1, 6-2 winner over Aliaksandra Sasnovich.
Meanwhile, 2017 Wuhan runner-up Ashleigh Barty is making sure she has enough left in the tank for a busy closing stretch of the season, including her singles debut at the WTA Finals in Shenzhen and a highly-anticipated Fed Cup final between Australia and France in Perth.
Barty is top seed at Wuhan and faces a stiff challenge in the fight for the year-end number one ranking from the likes of Karolina Pliskova, Simona Halep, Bianca Andreescu and Naomi Osaka.
The 23-year-old Australian is first-ranked this week and would like to finish the year on top, but admitted that she has other priorities.
"I think it's a target without being a target," Barty told reporters.
"We've put ourselves in a position where it's a possibility. I plan my schedule, the last six months of this year, well in advance. I think I'm not going to change it to try and chase it," she added.
"If it happens, it happens."
Barty will open her Wuhan campaign against either Russian Daria Kasatkina or Frenchwoman Caroline Garcia.