'It's about time he grew up' - Roy Keane offers scathing assessment of Man City's Jack Grealish

Roy Keane has claimed Manchester City star Jack Grealish needs to "grow up".

The £100m summer signing has been under the microscope since his British-record transfer from Aston Villa. In 17 Premier League appearances he has managed just two goals and as many assists for Pep Guardiola's side.

With the likes of Riyad Mahrez, Phil Foden, Raheem Sterling and Gabriel Jesus also competing for a place in Guardiola's frontline, Grealish has endured a frustrating start to life at the Etihad Stadium. Meanwhile, with his off-field antics drawing as much attention as his on-field performances, Grealish has found himself on both the front and back pages this season.

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When asked to comment on the England international's City career to date, Keane said the 26-year-old needs to put those incidents behind him and "grow up" in order to repay the faith shown in him.

Keane told ITV: "I think it’s crunch time for Man City over the next few months, this is where you will really test as a player, crunch games. Jack’s had a few injury problems, probably been criticised a little bit for his off-field stuff but I think what Jack has to do is grow up and get the trust of Pep.

"He probably hasn’t got that yet, same with England, I don’t think Gareth [Southgate] trusts him that much yet. Good opportunity for him [against Peterborough United]. Whatever Jack’s doing off the field, it does take its toll when you’re an attacking player, it’s another opportunity for Jack. I do think it’s about time he grew up."

Grealish returned to the starting line-up for the FA Cup fifth round clash with Championship strugglers Peterborough in his first start since the beginning of February.