The Red Devils have endured a testing couple of months under Mourinho in the Premier League, both in terms of results and squad harmony.
Manchester United lost to Brighton and Hove Albion and Tottenham Hotspur in two of their opening three Premier League fixtures to heap pressure on Mourinho.
The 20-time English champions slumped to a third loss of the campaign when West Ham thoroughly outplayed Manchester United in a 3-1 win at the London Stadium in September.
Mourinho’s side appear to have turned a corner over the past four weeks after a return of seven points in three games to make some progress up the Premier League table.
Manchester United were 2-1 winners against Rooney’s former club Everton last weekend thanks to goals from Paul Pogba and Anthony Martial at Old Trafford.
Rooney moved to DC United in the 2018 summer transfer window to end his long association with Manchester United following an underwhelming end to his Red Devils career.
However, the former Manchester United captain believes Mourinho retains the support of the Red Devils squad despite their patchy performances.
“Obviously they are going through a difficult period at the minute but Jose Mourinho is very experienced and I think some players have to do a little bit better,” Rooney told BBC, as quoted by the Daily Mirror.
“In my experience, I have never seen or heard of a player not wanting to play in the game because they have had a falling out with the manager.
“I don’t think as a player you could do that, you’ve got to respect the club and the fans and also respect your team-mates.
“I don’t think any player, certainly at Manchester United, will be not playing for Jose. I’m sure they’re all working hard behind the scenes to get results.
“Hopefully they can turn their form around, win a few more games and keep the pressure on the top of the table and get back up there, which is where we all want to see them.”
Mourinho took over the reins of Manchester United from Louis van Gaal in May 2016 after the Dutch coach failed to secure a top-four finish in his final season in charge.
The Red Devils have won the Europa League and the League Cup under Mourinho, while the Portuguese head coach has qualified for the Champions League in the last two campaigns.
Manchester United haven’t won the Premier League title since 2013 when Sir Alex Ferguson was still in charge, although Mourinho has won the top-flight title on three occasions.
The Red Devils are nine points adrift of leaders Manchester City and Liverpool FC in the title race.
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