The Portuguese has repeatedly complained about the FA and Premier League over TV scheduling.
United were recently picked to face Chelsea in their FA Cup quarter-final on a Monday night, with Europa League football the following Thursday and a trip to Middlesbrough in the Premier League on Sunday at 12pm.
Jose Mourinho outlined the repercussions for his squad, as Paul Pogba picked up an injury put down to a result of fatigue.
Sir Alex Ferguson has defended Jose Mourinho over his Thursday night complaints at Manchester United
Liverpool boss Jurgen Klopp has also defended Mourinho, having experienced similar challenges last term.
During Ferguson’s days in charge, United only featured in the Champions League as opposed to the Europa League, meaning their games were separated more evenly.
Since his retirement though, the Scotsman has had to watch his former side struggle with Thursday night football.
And on the Thursday fixtures for Mourinho’s United, Ferguson told ESPN FC: ”It's hard. It's very, very hard.”
Liverpool boss Jurgen Klopp has also lent his support to Jose Mourinho
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We were in three finals in four years. Now, the dominance is in Spain
Sir Alex Ferguson
However, the United legend highlighted how teams in England will bounce back in European football, with only Leicester left in the competition this season.
He added: ”I think success is cyclical. In the '70s, Ajax and Bayern Munich; '80s, Liverpool; '90s Italy, AC Milan. And then England had a great spell.
“We were in three finals in four years. Now, the dominance is in Spain. There's no question of that.
Jose Mourinho could have to contend with nine fixtures at Manchester United during April
"The same question could be asked about why is Bayern Munich not winning the Champions League, why the Italians are not winning it, why the French don't win it. At the moment, the cycle is with the Spanish teams. And they're best, that's why they're winning it.
"But it can change. [Cristiano] Ronaldo is older, [Lionel] Messi is older – can they replace those players? That will happen. And the cycle will change."
Manchester United could still be crowned Europa League champions and qualify for next season’s Champions League, with Anderlecht their quarter-final opponents.