And the 27-year-old will be given extra training to get him up to speed, although he could still be involved when St Johnstone visit Tynecastle on Saturday.

Levein said: "Let's say that he finished in November and he obviously he hasn't done any work between then and joining us, which frustrates me.

"And the best time to iron out any problems is as soon as they arise. I felt it was really important that he knows why he under-performed the other night, and he also didn't do enough in the Livingston game either to do what we needed to do.

"There is no point in pussy-footing round about it. People might think Scottish football is easy but it's not, the competitive nature of matches means that you have to be fit.

"So he apologised on Thursday. He is on a programme to improve his fitness and hopefully I don't need to speak to him again."

Stewart accused his former boss of "poor management" while former St Mirren and Rangers striker Steven Thompson claimed it was as "poor man-management as I've ever seen".

And Levein picked out his former signing as he brushed off the criticism.

"Listen, I have got to laugh," he said. "My good friend Mr Stewart, not intelligent enough or brave enough to try management. Why would I take any advice from him?

"It's like me taking advice on politics from somebody like, I don't know, Michael Stewart. So we'll just ignore what he says."

Levein insisted honesty was the best policy and felt the fans had a right to know what he felt.

"There has to be a line drawn," he said. "If there's a problem you have to address it and as far as I'm concerned the best time to do that is immediately. David accepted he hasn't turned up in good physical condition, he can get much fitter, and we're all on the same page.

"I would rather that than telling him he's doing well when he's not. That's the way I am with the players, at least they know they get the same thing consistently.

"There's no sides, I don't hold grudges or fall out with anybody, I say it as I think it is.

"I don't often do it publicly but I felt on this occasion it was important that our supporters know there is more to come from him. I don't want them judging him on his first couple of performances. They need to know as well that he has a long way to go before he is 100 per cent fit."

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