Ronaldo returned to United last summer and on an individual level it has been a successful homecoming, scoring 23 goals in 36 appearances at the time of writing.
But the club has endured a rotten season, currently sixth in the table with almost no chance of qualifying for the Champions League, while the Red Devils are currently going through seismic changes behind the scenes with Erik ten Hag set to take the reins in the summer.
‘Without Champions League football, United can get a year to totally rebuild and restart the process of remodelling the team, and Ten Hag can get used to the culture and get used to things,’ Berbatov told Betfair.
‘United need the right players for the positions and philosophy that Ten Hag wants to produce. So, get the right players in, make them the best players and get the club back to where it should be.
‘They will have to be strong and smart because talking about finishing in the top four as an achievement for a team like United, despite the ups and downs over the years, is an insult. They should be challenging City and Liverpool up there for the title.’
Berbatov was teammates with Ronaldo for one season, winning the 2008/09 Premier League title together, and the Bulgarian admitted he could see why the Portuguese player might opt to leave the club in the summer as he has been rumoured to do so.
He added: ‘I want Ronaldo to stay but I understand if he leaves. To have so many Premier League goals in a season at his age is an incredible achievement. He is doing what he needs to do, and that is score goals.
‘He has one more year at United, which is a good thing in my opinion, and now it is down to him whether he stays or leaves. I’d be glad to see him stay and continue scoring as well as helping the players around him.
‘Of course, things depend on the new manager and on what Ronaldo wants. He is an icon in football and when you are like that your opinion matters.
‘If he decides to go, obviously you cannot blame him. When you are used to playing Champions League football every year of your career and then you don’t have it, it’s tough to accept.
‘He will want to play as long as he can and show that the impossible is possible. He has proven that he can still do it at 37 in the Premier League, he likes to prove people wrong and I’m pretty sure that he will want to continue doing that and play a few more years.
‘When he stops it will be a sad day for football because he’s one of the true greats. That day comes for everyone.’
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