After seeing his side battle to a deserved point in a goalless draw against midlands rivals Stoke, McLeish reflected on injury setbacks for strikers Darren Bent and Emile Heskey.
Bent was expected to return to Villa's starting line-up in the Potteries after missing the home defeats to Liverpool and Arsenal with a thigh problem.
However, he failed to come through a morning training session unscathed and Villa subsequently suffered another blow when Heskey, after an encouraging first-half performance, was withdrawn with a recurrence of his Achilles injury.
A frustrated McLeish said: "We'll get them in and see who is injured, but Emile is definitely out now for a wee while.
"He's been up and down with his Achilles. We didn't think it was getting any worse, but he said it was intolerable when he came off at half-time.
"He had done a good job. He won a lot of balls in the air and battled away gamely, but it was half a game too far from him.
"We don't really know how long it will be. We'll find out maybe Tuesday night or Wednesday morning."
Bent's availability remains unclear ahead of Saturday's trip to Chelsea, with McLeish unsure whether the former Sunderland forward has suffered a new injury.
"He felt a twinge in the late session we had in the morning," added the Scot.
"It was restricting his movement and being a striker, a predator, you need to be mobile.
"We will scan him and if there's fluid there it's a fresh injury. If not, he shouldn't be too far away. A scan should let us know."
Should Bent be ruled out for any significant period of time, McLeish admits his options would be extremely limited.
"We definitely will be well down in terms of the experienced strikers, so we have to have a good think about that," he said.
Stoke were also forced to cope without their record signing as Peter Crouch remained on the sidelines with the virus that forced him to miss last week's defeat at Manchester City.
Dave Kemp, the Potters' assistant manager, explained: "He wasn't well. He's got a virus and he was taken ill after the Wolves game.
"He was better just before Christmas. He came in the training ground and we were hopeful, but (on the day of the match) he wasn't feeling good again.
"It's one of those things. We're looking to Saturday now (when the club play host to Wigan)."
Stoke manager Tony Pulis had earlier told Sky Sports: "We have to make sure Peter is well. He is such an important player for us. When he's ready we'll play him."