Louis Van Gaal and Manchester United Slammed by Jamie Redknapp and Roy Keane

Former Liverpool midfielder Jamie Redknapp believes Louis van Gaal's decision to leave Radamel Falcao on the Manchester United bench during the side's defeat to Arsenal was "staggering."

United fell 2-1 to their rivals in Monday's FA Cup quarter-final tie, ending their hopes of silverware this season. Danny Welbeck—who departed Old Trafford to make way for the on-loan Falcao at the start of the campaign—compounded Van Gaal's misery by netting the winner.

The manager decided to bring Michael Carrick, Phil Jones and Adnan Januzaj on, the last appearing a questionable judgement when United were in search of a goal. Redknapp doesn't understand the call, detailed in his Daily Mail column:

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The poor lad [Falcao] must be thinking: What am I doing here? I know he is not the player United thought they were getting, but isn’t it down to the manager to get the best out of him?

Goalscorers change games but instead they chased the match with Daley Blind and Michael Carrick, two sitting midfielders, on the pitch. Surely it would have been better to show greater intent by throwing on Falcao?

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Van Gaal's lack of faith most likely stems from Falcao notching just four goals in 21 appearances for United this season, per WhoScored.com. The Colombian works hard enough but has struggled to impose his physicality into matches, and his movement appears slower after his recent run of injuries.

United continued to lump the ball forward against the Gunners—reverting back to basics after Angel Di Maria was sent off—aiming to play off Marouane Fellaini's dominance in the air. Despite Falcao's poor form, many supporters will have been disappointed to see him sat on the bench in the exact situation he was signed to impact for the club.

Former Arsenal striker Ian Wright mocked Van Gaal's decision:

Football writer Daniel Storey believes the Dutchman got all of his changes wrong:

Jon Super/Associated Press

Ex-United captain Roy Keane pinpointed United's defence as the side's main weakness, telling the BBC (h/t Kevin Palmer of ESPN FC), "Big moments in a football match and if you give Arsenal, with the quality that they have, that type of freedom that's what happens. It was too easy, shocking. Absolutely disgraceful."

Phil Jones failed to clear the ball before Antonio Valencia's poor back pass let Welbeck slip in ahead of David De Gea, who could do little to stop the winning goal. Further comments from Keane were reported by James Whaling of the Daily Mirror:

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It was shocking defending. I was critical of the first goal [scored by Nacho Monreal] but that was even worse. United needed to do more, they never got going in the second half. I don't begrudge Arsenal the win. There is a time to play and a time not to—Phil Jones should have cleared it. Valencia compounded his first half error [in which he allowed Monreal to gain space].

I think the keeper can take Welbeck out of the game. He would get sent off but he could have made the sacrifice.

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Van Gaal's prospects now look bleak. United only have a top-four Premier League place left to play for, an achievement that is looking less and less likely by the week. The side's 10-game run-in includes matches with Tottenham, Liverpool, Manchester City, Arsenal, Chelsea and Everton, meaning further poor performances will be punished.

Failure to land a Champions League place will underline a season of total failure for Van Gaal, who will have come up short against all the club's goals. Although Keane wants to see him given "two or three years" to succeed, per BBC Sport, supporters are unlikely to be so forgiving if strange decisions continue to be made.