Manchester United fans will always love Roy Keane and Wayne Rooney for what the pair of them achieved at Old Trafford.

Keane is arguably United’s best ever captain; a force of nature who led by example on the pitch and demanded maximum effort - and often more than that - from all of his teammates.

Rooney, meanwhile, is United’s all-time leading goalscorer and a player who, particularly during the early years of his spell with the Red Devils, lit up Old Trafford with his extraordinary natural talent.

Keane was, of course, Rooney’s first captain when he joined United. The Irish midfielder skippered the club between 1997 until his unexpected departure in 2005.

After that, Rooney was captained first by Gary Neville and then Nemanja Vidic until 2014 when he was handed the armband by Louis van Gaal.

When Rooney slapped a wrestler in 2015

Although Rooney was undoubtedly declining as a footballer when he was made captain, he conducted himself with the utmost professionalism in his new role.

However, there was one incident in November 2015 which raised the eyebrows of some supporters.

Footage of Rooney slapping wrestler Wade Barrett at a WWE event went viral across social media and although it was all part of the show, some people felt he should have been focusing solely on his football - especially as he was flattering to deceive during matches.

Watch the video here…

How Roy Keane reacted

Two weeks after the WWE incident, Rooney produced an underwhelming performance in a 0-0 draw against PSV Eindhoven and Keane bought it up live on ITV Sport.

Here’s what he said…

“You look at Wayne’s legacy at Manchester United, it’s absolutely fantastic. His goals record - brilliant.

“But now he’s the captain, there’s a bit more responsibility and I think he’s got to do a lot more.

“I always question some players, what are they doing off the field. I saw Wayne last week getting involved in slapping a wrestler and I’m thinking ‘why is he getting involved in all that nonsense?’ There’s no benefit to him.

“I’d have a look at that.”

Asking if off-field issues were hindering his on-field performances, Keane added: “Well, it’s certainly not helping him!

“I wouldn’t begrudge a player for going out and enjoying himself but if you’re not at it yourself, you’ve got to look, and he’s got to lead by example and he didn’t do that tonight.

“He doesn’t look sharp, he looks off. Mentally he doesn’t look sharp, physically he doesn’t look in great shape, so he just needs to have a look at himself.”

Ouch.

Watch: Keane drops truth bomb about Rooney

Watch Keane's rant by skipping to 1:29 in the video...

We haven’t seen Rooney slap another wrestler since.

It just goes to show that Keane is never afraid to tell it like it is - even when he’s calling out his former United teammates - and that’s what makes him such an entertaining pundit.