The Red Devils limped over the finish line in the Premier League last weekend after a 2-0 loss to relegated Cardiff City at Old Trafford.
Manchester United finished the season in sixth place in the table following their disappointing defeat by Neil Warnock’s side at home.
Solskjaer’s side failed to end the Premier League campaign with a trophy following losses to FC Barcelona and Wolves in the Champions League and FA Cup quarter-finals.
Manchester United are facing speculation surrounding some of their biggest names, including club record signing Paul Pogba and Spain international David De Gea.
Former Red Devils skipper Rooney, who is the club’s all-time record goal-scorer, explained what Solskjaer needs to do to start to revive the 20-time English champions.
“It’s a tough one because to watch Manchester United struggle is always tough,” Rooney is quoted as saying by the Daily Star.
“When Ole came in, he did a fantastic job and you could see the players were given that bit of freedom and you could see they loved it and they earned the right to win game with how they were playing.
“But then all of a sudden, I don’t know whether it’s players being linked to other teams or players down tooling.
“I don’t think it is that but for some reason they just didn’t perform the last seven, eight games of the season, which has cost them.
“I think the players need to fear someone.
“They need to fear Ole Gunnar, they need to fear Michael Carrick – they need to respect them but fear them also.”
Manchester United haven’t won the Premier League title since back in 2013 when Sir Alex Ferguson was still in charge of the Old Trafford outfit.
The Red Devils have only managed to finish in the top four on two occasions in the past six seasons since the Scot’s retirement.
Manchester United will compete in the Europa League next term, having won Europe’s second tier competition for the first time back in 2016.
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