For many a year, it was always a stick used to beat Arsene Wenger with. His infamous 'I almost signed him' remarks never failed to raise the ire of long-suffering Arsenal fans.

The list of names the Frenchman had supposedly missed in his time with the Gunners truly makes for interesting reading: the likes of Cristiano Ronaldo, Lionel Messi and Yaya Toure, to name just a few.

But now the proverbial shoe is on the other foot. Reports have claimed Manchester United had Arsenal's summer arrival Gabriel Martinelli on trial a few times a couple of years ago, but the Red Devils passed on the chance to sign the Brazilian.

After scoring twice against Nottingham Forest in the Carabao Cup, the teenager was at it again in the Europa League on Thursday night, firing in a brace against Standard Liege.

Having seen his barn-storming display, United fans flooded to Twitter to share their thoughts about the young forward.

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Many supporters of the Manchester side insisted the 18-year-old is already proving himself to be a great player for their Premier League rivals.

Some Red Devils fans even suggested his performances put the club's own youngsters "to shame".

Check out some of the reaction of United fans below: