An off-colour Katie Boulter suffered a premature exit from the Wuhan Open in China as she fell to a straight-sets defeat to Ukraine's Lesia Tsurenko in the first round.
The British number one was beaten 2-6 5-7 by her more experienced foe, who entered the WTA 1000 tournament sitting 62 places below her in the rankings and also had to come through qualifying to earn a main-draw appearance.
Boulter had eased to victory over Tsurenko when the pair clashed in the first round of this year's San Diego Open, where the Briton won her maiden WTA 500 title, but she was a shadow of that player in Tuesday's contest as her 35-year-old foe earned a slice of revenge.
Boulter double-faulted six times over the course of the match - the same amount as Tsurenko - and only managed to convert three of the 10 break points that she fashioned on the world number 96's serve.
A topsy-turvy opening set saw just one hold between Boulter and Tsurenko in the first seven games, but it crucially came the Ukrainian's way as the British number one failed to hold serve once throughout the opener.
Boulter exit ends Great Britain's Wuhan Open hopes
After being broken five times in the opening set, Boulter finally gained some traction behind her own serve with a hold to love to start the second set, before her and Tsurenko traded breaks in the third and fourth game.
Both women subsequently missed a few chances to regain the upper hand, but Boulter's serve eluded her when she needed it most in the 11th game, as Tsurenko broke for the final time for a 6-5 lead.
The 35-year-old squandered her first chance to serve out the match, but on her second opportunity, Boulter sent a forehand long and hunched over in emotional anguish as Tsurenko advanced.
The Ukrainian - who now holds a 3-1 lead in her head-to-head with Boulter - will take on Magda Linette in the second round, and Boulter has now lost four of her last five matches in singles and doubles competition, also suffering defeat to Coco Gauff in the last 32 in Beijing.
The world number 34 was the only British player involved in the Wuhan Open main draw, as Emma Raducanu is currently out with a foot injury, while Harriet Dart retired in the first round of qualifying.
