Alex Neil, the Preston North End boss, admits he is unsure whether the decisive penalty in his side's 1-0 FA Cup loss at Sheffield United was the right call.
Blades skipper Billy Sharp won and converted a penalty in the 80th minute, after being brought down by North End skipper Tom Clarke, to secure the victory in a tightly contested game which saw little goal-mouth action.
And Neil admitted: "Obviously I'm disappointed, as you don't want to lose any game.
"Having said that, I don't think there was much in the game at all. I think the stats suggest that chances for and chances against are relatively similar.
"I think the disappointing thing is to go out to a contentious penalty. Having watched it back about six times, it's still a wee bit inconclusive for me. I'm not 100 per cent sure it was a penalty.
"I think the most frustrating thing leading up to it, is Jordan Hugill's free-kick that (the referee) gives against us at the halfway line. Ched Evans had been doing it to Paul Huntington all day.
"Having looked at it back, from the referee's position, I think it's really difficult for him to tell whether he plays the player first or the ball first."