Andy Murray is out of the Cincinnati Masters after a straight-set second-round loss to ninth seed Hubert Hurkacz.
Two-time champion Murray lost a tie-break in the first set before being broken late in the second by his Polish opponent.
Hurkacz served out for a 7-6 (7-4) 6-3 victory to book a place in the last 16.
"This week was fairly positive. I played much better than at Wimbledon and the grass season," said Murray, 34.
The 24-year-old Hurkacz will now face Spaniard Pablo Carreno Busta in a bid to make it to the quarter-final, as he looks to win a fourth career title.
Murray had eased past Frenchman Richard Gasquet in straight sets in the first round, while Hurkacz clinched a three-set victory over Alejandro Davidovich Fokina.
It was the first meeting on the ATP Tour between the two players.
Murray, a three-time Grand Slam champion and winner of this event in 2008 and 2011, was playing his first tournament since pulling out of the Olympic singles in Tokyo with a minor thigh strain.
The Scot has been added to the US Open main draw - where he won his first Grand Slam title in 2012 - which begins on 30 August.
Murray, who has also struggled in 2021 with a groin injury, added: "This week my body felt good, even if hardcourts are not easy on the body. Physically I was tired after some of the long rallies, but I felt fine."
Medvedev and Rublev celebrate victories
Top seed Daniil Medvedev made light work of opponent Mackenzie McDonald as he booked his place in the third round in Cincinnati.
The Russian, 25, cruised to a 6-2 6-2 victory against the 26-year-old American and will face Bulgarian former world number three Grigor Dimitrov, 30, next.
World number two Medvedev, who was runner-up at the US Open in 2019 and semi-finalist in 2020, secured his 12th ATP title at the Canadian Open last weekend.
It was a different story for Russian fourth seed Andrey Rublev, who needed three sets to overcome 2014 US Open champion Marin Cilic.
Rublev, 23, lost the opening set 7-5 to the 32-year-old Croat but regained his composure to secure the following two sets 6-3 6-1.
He will face either Australian Alex de Minaur, 22, or 34-year-old Frenchman Gael Monfils in the last 16.
Germany's Alexander Zverev, the third seed, beat Lloyd Harris of South Africa 7-6 (7-3) 6-2 and will face Argentine Guido Pella next.
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