Christophe Berra, Daryl Murphy and David McGoldrick are all fit and available for Friday’s live Sky game at Reading (KO 8pm), while Teddy Bishop and Kevin Bru will play for the U21s at Birmingham on Monday.
Murphy had been out with a calf problem, McGoldrick missed Ireland's games due to a groin injury, while Berra, Bishop and Bru had been out with hamstring problems.
"Daryl’s fine, David McGoldrick’s trained this week, none of them trained last week, those two were injured,” manager Mick McCarthy said. "Christophe Berra’s back after his hamstring, they’re all fit.
"Teddy Bishop is training, he’s fit, Kevin Bru is fit, but they won’t be involved this weekend, they’ll be playing in the U21s at Birmingham on Monday.
"If I need them then for the following games they’ll be fine, they’ll be back at it. We’ve got a full complement, it’s great.”
Full-back Jonny Parr played for the U21s earlier in the week and the only players still sidelined are Luke Hyam, who underwent knee surgery in the summer, and Luke Varney, who is set to sign a contract once he is over the torn achilles he suffered in the play-offs at the end of last season.
"We’ve got two long-term ones, Luke Hyam and Luke Varney, who are still in rehab, they’ll be back November time, that’ll be great,” the Blues boss added.