The Red Devils are in crisis mode after just eight games in all competitions in the current campaign.
Manchester United played out a 1-1 draw with Wolves at Old Trafford last weekend to lose further ground on their title rivals.
Paul Pogba came out in the aftermath of the stalemate with the promoted side to criticise Manchester United’s tactics.
Mourinho stripped the France international of the vice captaincy ahead of the Carabao Cup third round tie against Derby County on Tuesday night.
To compound the Portuguese coach’s misery, the Red Devils suffered a surprise 8-7 penalty shootout loss to Frank Lampard’s side.
Former Arsenal defender Keown criticised how Mourinho has handled the situation with Pogba.
“Mourinho should be building bridges with his players,” Keown told the Daily Mail.
“I remember at the start of the season when Manchester United lost 3-2 at Brighton and Mourinho said he would not criticise his players in public. Instead, after that defeat, it was actually Pogba who came out and said the players’ attitude at the Amex Stadium was unacceptable. That looked like the manager was handing responsibility to the players. I thought that was perfect.
“That’s why I had so much respect for Arsene Wenger, because he never criticised his players in public. The same went for Sir Alex Ferguson. They saved it for behind closed doors, like it should be.”
Manchester United are in seventh place in the Premier League table and eight points behind leaders Liverpool FC after six league games.
The Red Devils will make the long trip to take on West Ham United at the London Stadium in their next Premier League fixture on Saturday.
Manchester United haven’t come close to winning the Premier League title since their last success under Sir Alex Ferguson in 2013.
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