Wayne Rooney didn't speak very highly of Cristiano Ronaldo during his appearance on Sky Sports' Monday Night Football.

The duo enjoyed great success at Manchester United during their five-year spell as teammates.

However, that didn't stop Rooney from speaking honestly about Ronaldo's return to United.

Asked whether United's decision to re-sign Ronaldo last summer has worked out, Rooney replied: “You’d have to say no at the minute.

“I think he’s scored goals, he’s scored important goals in the Champions League early on in the season, he obviously scored the hat-trick against Tottenham, but I think if you’re looking to the future of the club, you have to go with younger, hungry players to do the best and lift Manchester United over these next two or three years.

“Obviously Cristiano is getting on a bit, he certainly isn’t the player he was when he was in his 20s, and that happens, that’s football.

“He’s a goal threat but the rest of the game they need more, they need young hungry players.”

Piers Morgan is one of Ronaldo's biggest fans. It is no secret that the 57-year-old believes Ronaldo is the greatest player to have ever played the game.

So, after Morgan saw Rooney's comments, he had to fire back at him. His tweet slating the Derby manager has gone viral, having picked up over 1.9k retweets at the time of writing. You can view it below...

He wrote: "A) Ronaldo’s scored 18 goals for Utd this season, in a poor side, aged 37. Last time Rooney scored 20 in a season for Utd, he was 27.

"2) Ronaldo’s still fitter now than Rooney ever was.

"3) There’s no footballer in the world with greater hunger than @Cristiano".

Fair to say Morgan doesn't quite agree with Rooney's thoughts about Ronaldo...

Ronaldo, despite being 37 years old, is having a decent campaign. He's been one of United's best players in what has been a tough season for the club.

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The Portuguese missed United's match against Leicester through illness but is back in training ahead of their clash against Everton on Saturday.

United are currently on the outside looking in when it comes to a Champions League berth. Ronaldo will be pivotal if they are to finish in the Premier League top four and qualify for Europe's premier cup competition.

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