Leeds United loanee and Millwall defender Charlie Cresswell underwent successful eye surgery on Monday morning.
Cresswell suffered a fractured eye socket after he was caught in the face by West Brom striker Daryl Dike in a goalless draw at the Hawthorns on April 1.
The defender is expected to be unavailable for the next five to six weeks, which looks set to see him miss the rest of the season for the Lions.