Irvine is yet to field summer signings Joleon Lescott, Georgios Samaras, Silvestre Valera and Sebastian Blanco.

Lescott has trained after a knee injury while Samaras, Valera and Blanco have all lacked match fitness.

And while Albion remain without a Premier League win this season, Irvine is prepared to throw them in against his former club.

"They are getting closer to where they would like to be, but the fact is we can't just wait before we expose these lads to first team football," Irvine said.

"We've had to throw in Brown Ideye and Jason Davidson before they were ready, but we had no choice.

"We will definitely have to bring players back before they are at the levels they need to be. That's the way things are, we're not really going to have much choice as far as that's concerned.

"It is an extra worry because you'd much rather put 11 players out there, and a group on the bench, who you knew were in peak condition.

"We have had to throw some people in, a little unfairly to them, where they've had to go in at the deep end."

But Irvine insisted he will not be reckless when it comes to risking the fitness of the players.

"It is, hopefully, a calculated gamble because we have plenty of information about them," Irvine said.

"They all wear heart rate monitors so we can tell exactly how they are feeling at the end of sessions. We can work out the training load and intensity.

"You are not relying on just your eye but you still use that to a large extent. You now have evidence to back it up.

"Everything we're doing is hopefully calculated rather than being on a whim."