Neil Redfearn is concerned over the fitness of Leeds midfielder Tommaso Bianchi.
Tommaso Bianchi returned to the Leeds United side against Reading, playing for the first time since the 2-0 away loss to Derby.
Neil Redfearn's side won 2-0 on this occasion but Bianchi did not last long, substituted after just 30 minutes for Casper Sloth, suffering a knee injury.
Prior to going off Bianchi had registered one shot on target and won three tackles for his side, also separately making three fouls.
Redfearn told BBC Radio Leeds: "Bianchi was playing really well before his injury.
"It's a bit of a whack and we're hoping not but we think he might have just opened up his ACL a little bit, so we'll have to see how that settles down."
An anterior cruciate ligament occurs when the joints become separated by twisting quickly at different angles, and there are more minor differing strains.
A diagnosis is not always instant, while Leeds fans will remember Roy Keane of Manchester United lying in agony on the turf when he tore his against the club in the mid-nineties, Arsenal's Theo Walcott was stretchered off for the Gunners last January smiling and joking with opposition fans, before it was confirmed days later he had suffered a severe injury which caused him to miss nine months of action.
After the game it was clear via Redfearn that Leeds could not say for sure one way or another, but he is sure to be assessed imminently and the situation will become clearer.
While there were groans from some fans when they saw the Italian's name on the team sheet, with the midfielder in poor form during December when he last featured, nobody will wish a severe injury on him, and with a bit of luck, Bianchi could miss days or weeks, rather than months.