The Red Devils were knocked out of the League Cup in the third round on Tuesday night when they lost to lower-league side Derby County on penalties following a 2-2 draw at Old Trafford.
Manchester United have struggled for consistent form in the Premier League this season as well, with the Red Devils having managed to pick up just three wins from their opening six games in the top flight.
There have been fresh rumours this week of a bust-up between Mourinho and Paul Pogba at Old Trafford as the pressure continues to mount on the Portuguese coach.
And former Arsenal star Keown feels that Mourinho seems to have fallen out with some of his key players at Old Trafford.
Speaking to BBC Radio 5 live, Keown said: “Jose seems to be at war with his players and he needs to start seeing the good in what they do,” Keown told BBC Radio 5 live.
“Is he pulling up the handbrake?”
He continued: “Everyone in the media is quick to turn this into a massive crisis.
“Manchester United have had some good away results but suddenly they’re not able to win at home. I don’t enjoy seeing them not being competitive.
“Mourinho has said the pundits on the sofa have got too much to say. One of them, Frank Lampard, has proved him wrong. It’s a great scalp.
“This was a really good United team and I can’t think of many bigger shocks in their history. Mourinho tried to go for it and he’ll be hurting in the dressing room.”
Manchester United will attempt to dust themselves down as they prepare to return to Premier League action this weekend with a trip to West Ham United on Saturday lunchtime.
The Red Devils ended up in second place in the Premier League table and without a trophy under Mourinho last season.
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