Roy Keane accused Manchester United of ‘disrespecting’ Cristiano Ronaldo after the legendary forward was left on the bench during Sunday’s 6-3 defeat to Manchester City.Keane then got into a heated debate with his Sky Sports colleague Micah Richards over the 37-year-old.Erik ten Hag made five substitutions during Sunday’s Premier League clash at the Etihad Stadium but decided against using Ronaldo, arguably the greatest goalscorer in football history.The Dutchman raised eyebrows after the match by claiming that he left Ronaldo on the bench out of respect for the Portuguese superstar’s illustrious career.Get your Paul Scholes 'He Scores Goals' T-Shirt here

What did Roy Keane say about Man Utd and Cristiano Ronaldo?

Keane feels that there could be trouble ahead for Ten Hag if he continues to bench Ronaldo, who wanted to leave Old Trafford in the summer after United failed to secure Champions League football for the 2022-23 campaign.

The former Man Utd captain also said that it’s “ridiculous” that Ten Hag isn’t using him more and believes United should have let him go.

"I think it's ridiculous for a player of his stature, for Man United to just keep him [on the bench]," Keane told Sky Sports.

"Even today, could he have brought him on? Of course, he could've brought him on. So what if you're 4-0 down. If you look at his goalscoring record, he has as good a chance as anyone of putting the ball in the back of the net.

"People obsessed with the pressing side of the game... If you put the ball in the right areas, he'll score goals."

Cristiano Ronaldo was an unused sub against Man City

MANCHESTER, ENGLAND - OCTOBER 02: Cristiano Ronaldo of Manchester United looks on ahead of the Premier League match between Manchester City and Manchester United at Etihad Stadium on October 02, 2022 in Manchester, England. (Photo by Laurence Griffiths/Getty Images)

"Man United are showing disrespect to Ronaldo," he added. "I think he should've been let go before the transfer window [closed].

"I think the manager holding onto him, okay, you say you need options, but if you don't hold onto Ronaldo to sit on the bench He's one of the greatest players ever, he had options, this idea that he had no options is rubbish. He did have options, four or five very good options.

"Okay, today, the manager brought [Anthony] Martial on, who scored two, so yeah that's justified. But generally speaking, the bigger picture, he's not going to play Ronaldo, we know that. He's played in one or two European games, it's just going to get uglier as the season goes on. Okay, Ronaldo's motivated with the World Cup coming up. But if he's sitting on the bench for Man United week in week out, it's not good."

Cristiano Ronaldo warming up for Man Utd v Man City

MANCHESTER, ENGLAND - OCTOBER 02: Cristiano Ronaldo of Manchester United warms up ahead of the Premier League match between Manchester City and Manchester United at Etihad Stadium on October 02, 2022 in Manchester, England. (Photo by Laurence Griffiths/Getty Images)

Video: Roy Keane slams United for ‘disrespecting’ Ronaldo

Watch the clip here:

When Richards argued that Ronaldo doesn’t suit the way Ten Hag wants to play, Keane was having none of it, pointing to the fact that Cristiano scored 24 goals in 38 games for the Red Devils last term.

Video: Keane and Richards’ heated debate over Ronaldo

Watch the clip in full here:

Ronaldo has only managed to score one goal in eight games so far this term and will surely be looking to move on in January unless Ten Hag starts to play him more regularly.

Read more: Man City 6-3 Man United: Cristiano Ronaldo and Sir Alex Ferguson’s faces said it all