Rio Ferdinand has trolled younger brother Anton on social media after Manchester United picked up a crucial win over top-four rivals West Ham.

In an Old Trafford showdown that looked to be heading towards a goalless draw, Marcus Rashford scored to clinch a 1-0 victory deep into added-time. It was his second goal in as many games after coming off the United bench.

That winner was not without question marks, though, as Edinson Cavani beat the offside flag after linking-up with wantaway France striker Anthony Martial — another replacement used by interim manager Ralf Rangnick.

The flag stayed down and Rashford tucked home the winner on Saturday afternoon. It was a result that moved United up to fourth-place as the intense battle for Champions League qualification gathers pace.

United are, of course, not going to catch Manchester City and Liverpool in the race for the title, but gain ground in the top four battle after Arsenal and Tottenham also dropped points.

Taking to social media post-match, former West Ham defender Anton Ferdinand — who progressed through the same system as Rio in east London — posted a screenshot of the Martial to Cavani pass, claiming offside.

Venting his frustrations with two angry face emojis, he added the caption: "How is this not offside?

"VAR is so inconsistent it's a disgrace."

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And ex United man Rio couldn't resist the chance to take aim at his younger brother after being prompted by several United supporters.

Addressing his 11.2million followers on Twitter with a wide eyes and laughing face emoji, Rio said: "I'm afraid it was judged onside bruv..."

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