"He has suffered a fibula fracture which needs surgery and (he) will miss approximately three months," Sevilla said in a statement.
Nolito, 32, has only played three league matches this season but scored and provided two assists as Sevilla beat Athletic Bilbao 3-1 on Thursday in the Copa del Rey.
Sevilla visit Athletic in La Liga on Sunday as they bid to cut the gap on leaders Barcelona, who host Eibar, to four points.
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(Reporting by Rik Sharma; Editing by Ken Ferris)
