James McCarthy has reportedly been left exhausted by the pace of training, as it's claimed manager Ange Postecoglou didn't have a big role in signing him.
The Republic of Ireland international made his first start against Livingston on Sunday but struggled to make an impact, completing just 84.5 per cent of his passes.
The 30-year-old has signed a four-year contract with Celtic, but it's reported that he has been struggling with Postecoglou 's training sessions.
The Athletic states that the pace and intensity at Lennoxtown has proved difficult for McCarthy, with questions also raised about the recruitment process.
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