Marouane Fellaini's injury-time header gave Manchester United a 2-1 win in Arsene Wenger's last game at Old Trafford with Arsenal
 Substitute Fellaini popped up in the 91st minute with a well-directed header from Ashley Young's left-wing cross to give Jose Mourinho the points over rival Wenger, who hasn't won a league game at Old Trafford since 2006
Paul Pogba had given United the lead (16) from close range, but former United midfielder Henrikh Mkhitaryan levelled after the break (51) with a neatly-placed low effort from the edge of the box
Arsenal nearly held on, but the result means United are guaranteed a top-four finish in the Premier League, and need just four points from their last three games to secure second place
Arsenal are sixth, three points above seventh-placed Burnley with a game in hand, but the defeat confirms they cannot reach the top four, and will finish below north London rivals Tottenham for the second successive season
Wenger made seven changes ahead of the Europa League semi-final second leg on Thursday at Atletico Madrid, giving Konstantinos Mavropanos his debut in defence
United got back to business on the pitch and were ahead on 16 minutes through Pogba
Alexis Sanchez saw his header from point-blank range superbly diverted onto the post by Hector Bellerin, but Pogba was on hand to poke into the empty net from three yards
In what was a competitive first half, Mkhitaryan came close to equalising against his former club moments after the opener, but dragged inches wide of the far post from 20 yards after Ainsley Maitland-Niles' backheel
But after Romelu Lukaku was taken off injured after the break, Mkhitaryan made it second-time lucky, striking through the legs of Victor Lindelof and into the bottom corner from 20 yards
At the end of an uneventful second half, United thought they had won it when sub Marcus Rashford deflected the ball home from close range after Fellaini's header had ricocheted off the post, but he was rightly flagged offside
United did win it moments later through Fellaini, who rose highest in the area to meet Young's fine cross and loop a header into the far corner beyond the grasp of David Ospina
: "If it was a draw it wouldn't be unfair
 They did a good game
 No pressure for them, they defended well and of course we were the team that tried to win and had a few more chances
 We were a bit lucky when we scored in the last couple of minutes, but were stronger in the last 20
" "Overall the team performance was very positive for such a young team and of course they are very disappointed in the dressing room because they gave everything
 You could see in the last 20 minutes some of them are not used to that pace and intensity
 It's difficult to find a bad performance in the team, but we had a bad result
"There were a handful of positives for Arsenal to take away from Old Trafford, in particular Maitland-Niles' role in midfield
He won possession five times, and covered the second-most ground in the Arsenal side, completing 36 of his 39 passes
The 20-year-old referenced how Wenger had been like a father figure to him, and Arsenal will be hoping the Englishman pushes on under the new boss in the coming seasons
Arsenal now go to Madrid for their Europa League semi-final second leg clash on Thursday, while United travel to Brighton on , live on 
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