Madison Keys, the 2017 U.S. Open runner-up, and Borna Coric withdrew from Wimbledon on Saturday because of injuries.
The tournament begins Monday.
Keys, an American who was seeded 19th at the All England Club, pulled out because of a hurt abdominal muscle.
She was replaced in the field by Coco Vandeweghe, twice a quarterfinalist at Wimbledon and twice a semifinalist at other Grand Slam tournaments, who lost in qualifying this week. Vandeweghe's first-round opponent will be No. 17 seed Elena Rybakina.
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Coric is a Croatian who got into the field thanks to a protected ranking because he has been injured. He cited a shoulder problem for his withdrawal.
He was drawn to face No. 12 seed Diego Schwartzman and that spot will be filled by an as-yet-unannounced player who lost in qualifying.