Manager Paul Lambert believes Saturday's home game against Accrington Stanley will probably come too soon for Jon Nolan and Janoi Donacien, while Teddy Bishop and Freddie Sears are not yet ready to start a League One game having recently returned from long-term injuries.
Nolan has been suffering with a heel problem, while Donacien, a former Stanley player, has been out with a dead leg he picked up in the 5-3 defeat at Lincoln.
"Nolan is probably the most doubtful one of the two of them,” Lambert said when asked about the pair.
"Janoi has started training, so we’ll see how they are this morning, but this one might just be a bit early for them.”
Lambert says Nolan’s problem shouldn’t be a long-term issue: "No, I don’t think so. He trained a little bit the other day and it’s just his heel that’s giving him a little bit of a problem.”
Bishop made his first start of the season at Exeter in the Leasing.com Trophy last week and impressed, however, Lambert says he’s not yet ready to be named in a League One XI.
"No, he’s been out for months,” he added. "He’s done really well to get himself back in, but he’s been out for a hell of a long time.
"It’s great to see him back because he’s different to what we’ve got, but he still needs a little bit of time. It’s the same with Freddie Sears’s situation.”
Left-back Myles Kenlock made a decent return to the team at Exeter and Lambert was asked if he had considered returning to the early-season left-hand side with Luke Garbutt pushed into midfield ahead of the Londoner.
"Myles has found it hard because the form of Garbutt has been unbelievable,” Lambert said. "He’s scored six for us from left-back and his set plays and things like that.
"It’s been tough on that side of it. Myles is pushing and if he keeps doing what he’s doing, let’s see if he can get back in.”