Leeds midfielder Adam Forshaw will miss the rest of the season after fracturing a kneecap in training.
It will take the 30-year-old midfielder six weeks to recover, and Leeds' last game of the season is at his former club Brentford on 22 May.
Fit-again England midfielder Kalvin Phillips will return to the starting line-up at Crystal Palace on Monday.
"It's painful for us because he [Forshaw] is important," said Leeds boss Jesse Marsch.
"The main thing is that Adam is one of the guys who gives more to the group and does everything he can to think about the team first.
"He'll still be around and will still be a big part of the group.
"It should be a relatively straightforward recovery, so by the summer he should be ready to go."
Forshaw returned from a long-term hip injury earlier this season and has made 23 Premier League appearances this term.
Leeds are five points above the relegation zone with six games to play, with Palace four points above them in 14th place.
Marsch confirmed that Phillips will make his first start since 5 December after a long-term hamstring injury.
The 26-year-old came off the bench in Leeds' past two games, a 1-1 draw with Southampton and 3-0 win at Watford.
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