roy keane has urged manchester united fans to give louis van gaal up to three years to prove himself at the old trafford helm the dutch manager oversaw another disappointing performance and result in united's 2 1 fa cup defeat by arsenal at old trafford on monday night danny welbeck returned to his old stomping ground to score the winner after wayne rooney levelled nacho monreal's strike in the first half, but it was yet another lacklustre display under van gaal that irked united supporters united's legendary midfielder roy keane says louis van gaal should get more time in charge at old trafford  van gaal came under more criticism for another lacklustre display in the 2 1 fa cup defeat by arsenal  keane was in the studio with former england stars gary lineker, alan shearer and ian wright  their hero keane, however, maintained the manager needs more time with fans unaware of what the job entails 'van gaal is going to get criticised, you'd expect that,' keane said during his bbc match of the day analysis 'give the man a chance   two or three years a lot of fans don't quite understand how to run a football club as big as manchester united 'they should have given david moyes more time but didn't what are they going to do? chop and change again? van gaal has been in the door two minutes it takes time it's literally a rebuilding job a dismayed marouane fellaini (left), michael carrick (centre) and wayne rooney after arsenal's winner  danny welbeck broke the hearts of his boyhood club by pouncing on an error to send arsenal to wembley  'it would be a disaster if united don't finish in top four the big problem with people at the club and ex players is they keep looking back comparing teams from 10 years ago 'they have got to look forward focus on the players, focus on the manager get right behind him i still think they have enough to get in that top four' keane's old sparring partner, former newcastle and england striker alan shearer, was more damning he said: 'manchester united's main priority this season is finishing in the top four if they don't then it will be a catastrophe 'they have spent a lot of money on players there's a hell of a lot more money that needs to be spent to get them anywhere near where they want to be 'there isn't another team in the premier league that passes it back more than manchester united' wayne rooney's flying header to equalise for united in the first half couldn't stop his side crashing out  angel di maria's red card was the final blow for united as van gaal's troops lost their heads  keane and shearer's battle of words during the bbc's fa cup analysis were nothing compared to what the hot headed duo got up to in their playing days neither was a player the opposition wanted to get on the wrong side of, so no battle was more fierce than when the two clashed keane lashes out at shearer when the two came to blows at st james's park in 2001  the former united captain named shearer as a player he 'always had in the back of his mind' in his recent autobiography the second half alongside other famous foes like patrick vieira and alf inge haaland keane made it clear that although he regularly came across alan shearer while working as a tv pundit, there is little or no chance of them ever building bridges such is the mutual dislike of each other keane picked shearer out as a player he always had in the back of his mind alongside patrick vieira  the most famous flashpoint came in 2001 at st james' park the two skippers came head to head and keane was shown a red card for lashing out at the england man it was the first time the former united maestro had appeared in the bbc studio after a long association with terrestrial rivals itv keane has to be held back by david beckham during the infamous row that saw the united man sent off 
manchester united van gaal danny welbeck arsenal the fa cup keane united
keane: 'fans don't quite understand how to run a club as big as united' van gaal oversaw another poor performance in the 2 1 defeat by arsenal  danny welbeck came back to haunt united by netting the winner  united now have no chance of silverware after crashing out of the fa cup  read: van gaal walks out of man utd press conference on a sour note  click here for all the latest manchester united news 