The Red Devils edged to a 1-0 win over Young Boys in the Champions League on Tuesday night to book their place in the knockout stage with a game to spare.
Manchester United made hard work of their mid-week tie and Marouane Fellaini didn’t score a winner until the first minute of added time at Old Trafford.
Mourinho was heavily criticised for his reaction to Marcus Rashford’s miss during the 1-0 win, before he reacted angrily to Fellaini’s last-gasp winner.
The 20-time English champions will make the long trip to Southampton in the Premier League on Saturday evening in search of a first win in three top-flight outings.
Manchester City were 3-1 winners against Manchester United before the international break and Crystal Palace secured their first-ever point at Old Trafford in a 0-0 draw last weekend.
Mourinho has been under pressure throughout most of the Premier League season, having won six of their opening 13 games in the Premier League season so far.
Ex-Real Madrid boss Zinedine Zidane is one coach who has been linked with the Old Trafford role.
Former Manchester United defender Ferdinand warned the Red Devils that there aren’t many options available to replace Mourinho.
“Who’s the replacement?” Ferdinand told BT Sport. “I don’t see Manchester United sacking Jose Mourinho without a ready-made replacement to step into that role. And I don’t think there is one out there.
“An idea of who you can get, who’s gettable now? Who’s not in a job now? Zinedine Zidane yes, he’s an obvious one. But I don’t know, listen, it’s a difficult situation.”
Manchester United have lost to Brighton, Tottenham Hotspur, West Ham and Manchester City in the Premier League this season.
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