Philippe Clement confirmed Vladan Kovačević is still out with concussion and gave further squad updates ahead of Saturday's Sky Bet Championship clash against Portsmouth.
"Vladan (Kovačević) is not back yet, so that I can say.
“Ante (Crnac) will play this evening (under 21s) to get minutes, to get rhythm, I think it's important for him to get up to speed.
“Mirko (Topić) and Bruno (Alves) will play the game this evening. It's against a good opponent here in home game. So, I think a good situation for them to step up again.
“Yeah, Kellen (Fisher) trained today. Of course, it was a very, very soft session. It was light, but he felt better again. So, he can be in contention for the squad."
Clement shared his reasonings for putting players in the under-21s squad this evening and his substitution choices on Wednesday evening.
He added: "It’s a difficult decision to make, because, okay, you have friendly games, but it's a different rhythm of the game.
“You have training sessions, but not too many. It's never at the intensity of a Championship game and you need to bring them back.
“It's on me. It was maybe not the best decision to put Ante on the pitch in those circumstances, but you look what are the available offensive players in that moment with players like Papa (Diallo) out and Ali (Ahmed) out.
“He clearly needs also more rhythm, he needs more game time, but it's a normal thing after being 10, 11 months out. So those are difficult decisions to judge before the game and before you see it.
“Jovon (Makama) can start games, but he will not end games when he starts.
“But clearly he had an impact on the game also in the minutes that he played and he created together with the team three opportunities.
“He's not there where he was last season and that's normal but we need to get him up to speed here.
"Jacob (Wright’s) energy was running low, and you have a game every three days. So again, the story and I don't want to repeat 1,000 times, but we have a lot of players still in that situation.
“A lot of players have never played at this level every three days because they're young, because they're stepping up.
“I'm super positive about him and the evolution he's making.
“But we still need to manage those moments when his battery runs low one moment and that you need to make decisions around that."
The head coach also took time to thank the fans for their support at Wednesday's game and highlighted the significance of Saturday's fixture as the club pays tribute to Michael Wynn Jones.
"I thought our fans were really good last game, from the start until the end and I understand that there are people after the game disappointed," he concluded.
"They gave everything to the team, what I asked before the game, and that was to keep on supporting the players on the pitch because it helps a lot and they did.
"It's a really special game also, this one. Delia will be back for the first time, so it's going to also be an emotional game around that.
"The biggest thing that I wish is to give Delia the three points. That would be the best present we can give her in these difficult times."