They say that recent Manchester United managers have left the club looking a decade older than when they arrived, and after just 56 days in the hot seat, Ruben Amorim is already cracking jokes about how it is changing his appearance.
The 39-year-old was the club's youngest appointment since Wilf McGuiness followed Sir Matt Busby in 1969, but after his first couple of months in the job saw United lose six of their 11 games and plunge head-first into a relegation battle, Amorim is seeing the ageing process take hold.
His counterpart across the city, Pep Guardiola, recently suggested that he was struggling to sleep and couldn't digest food, so concerned was he with stopping the rot at Manchester City.
Guardiola and Amorim could certainly compare notes on a sleepless night or two, given the travails of their teams at the Etihad and Old Trafford in the last two months.
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