Oxford United defender Johnny Mullins has been ruled out for the rest of the season with a stress fracture of the metatarsal, reports BBC Radio Oxford.
Mullins, 28, injured his ankle in the 3-0 defeat by Chesterfield on 15 March and has not played since.
The former Rotherham man has made 41 appearances for the U's this season, scoring four goals.
"He is an important player for this club and a good player at that," manager Gary Waddock said.
His absence is a huge blow to Oxford United's play-off aspirations and for new manager Waddock.
"We will miss him now for the remaining fixtures and we wish him a speedy recovery but it is part and parcel of football that you get injuries."