Naomi Osaka has been knocked out of the second round of the Madrid Open by Karolina Muchova 6-4, 3-6, 6-1.
The world number two was overpowered by her Czech opponent in one hour and 49 minutes on Sunday. For Muchova, it is her tenth win over a top five player in her career.
Osaka double faulted on break point which saw Muchova go 2-1 up in the opening set. Muchova saved the only break point she faced in the following game before going on to comfortably seal the opener.
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Muchova, who knocked out Ash Barty at the Australia Open in January, was not done there as she took another early 2-1 lead in the second set, but Osaka broke back to level the set at 3-3 with a powerful forehand.
Momentum swung in favour of the Japanese player, who knocked out compatriot Misaki Doi in straight sets in the opening round, and she won five successive games to force a decider.
But world number 20 Muchova regained her control and took an early break at 1-0 before cruising to a third set victory, booking her place in the last-16.
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