Abdominal muscle problems which developed overnight on Wednesday forced Nick Kyrgios to withdraw from his ATP Mallorca match against Roberto Bautista Agut.
The Australian drawcard was competing for a third consecutive week on grass, having reached the semi-finals at Stuttgart and Halle.
He will now be under the cosh to regain fitness with Wiimbledon starting on Monday.
“I have been playing a lot of great matches lately and unfortunately I woke up with a pain in my abs,” Kyrgios said.
“I went to see the tournament doctor right away and he advised that I don’t play tonight.
“I will follow his advice as I don’t want to risk Wimbledon next week.”
Kyrgios added: “I was really looking forward to tonight’s match as I’ve been loving my time here. Mallorca is such a beautiful island with really nice people.”