Roberto Martinez does not expect Wigan's on-loan Arsenal winger Ryo Miyaichi to play again this season.
Miyaichi was hurt after coming off the bench during Saturday's FA Cup quarter-final win at Everton.
His scan results are not yet back, but Martinez is planning for Wembley and the relegation run-in without the 20-year-old.
Japan international Miyaichi, who joined on a season-long loan last summer, spent three months out around the turn of the year with a different ankle problem.
Wigan's Twitter feed carried Martinez's latest bulletin and also said an injury suffered by Callum McManaman at Goodison Park was not serious.