The below par Whites were thumped 4-0 but will need to pick themselves up quickly as they entertain fellow strugglers Nottingham Forest on Friday night in a match that could have a major bearing on the relegation picture.
The Yorkshire side remain six points clear of the bottom three as rivals for the drop West Ham lost 3-2 at Chelsea after holding a two-goal lead.
Pre-match Leeds boss Daniel Farke, whose side had only lost one of their last ten games, flagged up the importance of dealing with the Gunners’ expertise at set-pieces.
United, who faced a dozen corners, were unable to totally cope as both first-half goals stemmed from flag-kicks.
After a bright opening by Leeds, the London side took a firm grip of proceedings. They smothered the United midfield, Dominic Calvert-Lewin got little change out of his markers and Farke’s men could make little progress down the flanks. Arsenal had an answer to everything Leeds tried in attack.
Mikel Arteta’s team made the breakthrough on 27 minutes when Leeds only partially cleared the ball from a corner. Noni Madueke, only starting because Bukayo Saka was injured in the warm-up, crossed perfectly back into the area where Martin Zubimendi headed past Karl Darlow.
Ten minutes later the game was effectively over. Madueke’s corner created panic in the defence at the near post where a couple of Leeds players and Darlow went for the ball, the Welsh keeper punching the ball into his net.
Farke changed his system at half-time in an attempt to get a foothold in the game by sacrificing defender James Justin for attacker Noah Okafor.
For about 20 minutes the Whites started to ask questions of the Gunners backline without testing goalkeeper David Raya but the tactical change meant Arsenal had more space up front.
After weathering United’s mini-storm, Gabriel Martinelli delivered a dipping cross to the far post where Viktor Gyokeres shinned the ball in on 69 minutes after getting in front of Jayden Bogle.
Despite more substitutions Leeds faded badly after that and Arsenal crowned a strong effective performance near the end when Gabriel Jesus cleverly created space to baffle marker Pascal Struijk and slot home.
A disappointed Farke said it was important his squad did not dwell too long on the defeat.
“We faced today the best side currently in Europe. There are reasons why this team is sitting top of the table in the Premier League and why this team is the best team currently in Europe - eight wins out of eight Champions League games.
“You need a perfect day in order to give yourself a chance and also a bit of luck that this side perhaps is not there with their best day and not super effective. We didn’t have our very best day and they were on it from the first to the last second.”