Steve Evans has seemingly confirmed that he may be forced into at least one change from Thursday's win.
The 24-year-old had to be replaced on the half-hour mark of the Whites' win over Wolves on Thursday shortly after receiving medical attention, having been well off the pace during the opening stages of the game against Kenny Jackett's side.
Evans confirmed that he already knew before the midfielder was attended to by his medical staff that he would have to be replaced, and explained that he believes that Adeyemi has contracted a virus.
"I thought he looked absolutely on his feet after five minutes. He couldn't track one of their runners and I made the substitution," Evans told the Yorkshire Evening Post.
"The medical team went over and said 'he's feeling a little bit lethargic but he's fine' but I had made my decision before the medical staff went on.
"That big fella has obviously got a little virus in his system or something like that because he has been awesome in the times he has played apart from one other game."
Although United would go on to win the game - having been a goal behind when Adeyemi was replaced by Souleymane Doukara - largely thanks to the enforced tactical reshuffle, the on-loan midfielder will be a big loss for Evans' side, should he miss the Preston clash.
His energy has made him an important member of Leeds' midfield this season. And while he is predominantly considered a defensive midfielder, he has shown that he can be a handful from set pieces, with both of his goals - including what would turn out to be the winning goal against Hull earlier in the month - coming from corner routines.
If Evans decides to replace Adeyemi with another midfielder, then it seems likely that either Alex Mowatt or Luke Murphy - who both started on the bench at Molineux - will get the nod. However, given the success following the substitution, it would not be a surprise if the manager decided to use the system United deployed once Doukara had come on.