United have started the season poorly in the Premier League, losing against Brighton and Tottenham in between wins against Leicester City and Burnley, to fall six points behind the early frontrunners.
Mourinho has faced criticism for the team’s negative performances and playing style, amid reports of a divided dressing room and a rift with the club’s chief executive Ed Woodward.
According to Crooks, who had a loan spell at Old Trafford during his playing days, the 55-year-old coach has been negatively affected by the looming figure of Zidane, who has been linked with his job.
He told BBC Sport: “I have a strong suspicion the spectre of Zinedine Zidane might have a lot to do with Mourinho’s anxieties.
“To get so emotional in a news conference in a bid to remind journalists who he is and what he has done in the game is unnecessary – we know what he’s done – but suggests their relationship is at breaking point.
“What Mourinho must protect at all costs is his relationship with his players and the Manchester United board. Get that wrong and it’s curtains.”
Man United produced a much-improved display in their 2-0 win against Burnley at Turf Moor on Sunday, however, only time will tell whether or not Mourinho can turn things around enough for the team to mount a genuine title challenge in the coming months.
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