QPR fear Jordan Cousins faces a long spell out with a serious knee injury after he was stretchered off during the home defeat against Blackburn.
Rangers were beaten 2-1 at Loftus Road, where Cousins was in obvious distress as he was carried from the pitch early in the second half.
He fell awkwardly after an accidental collision with team-mate Bright Osayi-Samuel as they challenged Blackburn’s Lewis Travis near the halfway line.
The injury will be assessed over the next 24 hours but the initial signs are not good.
Caretaker manager John Eustace said: “There’s no news at the moment but it certainly looks a bad one. We’ll have to wait and see on that.”
Danny Graham’s 22nd-minute penalty put Blackburn ahead and Bradley Dack doubled their lead just 29 seconds into the second half.
Matt Smith headed in Luke Freeman’s injury-time cross to pull a goal back for QPR, who are still not mathematically safe from relegation.
Osayi-Samuel was lively for them but missed chances, while Rangers were punished for some sloppy defending.
Eustace, placed in charge following the recent sacking of Steve McClaren, said: “I’m disappointed with the performance but the attitude of the lads was fantastic. They kept going.
“The most disappointing thing was the goals we conceded – poor decision-making. We also created a lot chances and it’s disappointing we didn’t take them.
“We’ve made two really poor decisions for the goals and started the second half so sloppily. But the attitude of the boys was good, which it is every week.
“Blackburn are a very streetwise team and we knew it would be tough for us today, but we needed to take the chances we created.
“We’re down to the bare bones and had to change the back four, but that’s certainly not an excuse. We weren’t good enough.
“It’s up to the players who put the shirt on to go out and play well.”