Manchester United have just unlocked the key to giving Kobbie Mainoo his sparkle back

Kobbie Mainoo had a smile on his face and was in a playful mood on Tuesday night.

When Mainoo walked out of the tunnel, he tapped Noussair Mazraoui on the right shoulder and the defender quickly turned around, thinking it was Joshua Zirkzee who had done it.

Mainoo burst out laughing and appeared to say "it was me," to Mazraoui. The youngster was named on the bench against Barnsley in the third round of the Carabao Cup, but he was in high spirits and should greatly benefit from the opportunity to have a rest ahead of the weekend.

This time last year, Mainoo was still recovering from an ankle injury that he sustained in pre-season and his last 12 months have been nothing short of extraordinary.

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Mainoo has become a first-team star, the club have opened talks to give him a new contract to reflect his new-found importance and he was brilliant for England during the latter stages of Euro 2024.

The 19-year-old's rise has been sensational and not a surprise to those who know him best, but it has inevitably come with an increased workload and higher expectations.

Since making his full Premier League debut at Goodison Park last November, Mainoo has been played in almost every United game and his season was extended due to England duty.

Mainoo has been on the go for a long time and although he was given an extended break in the summer after England reached the final of Euro 2024, he still had less time to reset and recharge ahead of the new campaign than players in the squad who didn't play for their nations.

A source close to Ten Hag conceded that Mainoo had been overplayed last season but said it was