Olivier Giroud came off the bench to snatch Arsenal a point against a dominantManchester United side in Saturday's lunchtime showdown.
The Frenchman's header was cruel on Jose Mourinho's team, who had deservedly lead thanks to Juan Mata's neat strike early in the second half.
The home side, as expected, were missing several first-team regulars, including top scorer Zlatan Ibrahimovic through suspension. Marcus Rashford was chosen to fill in as the main striker, as Wayne Rooney started on the bench.
The Gunners meanwhile were relieved to see Alexis Sanchez passed fit, whilst Theo Walcott also featured despite doubts over his availability. Arsene Wenger's men were looking to end a wretched record at Old Trafford, where they had failed to win in the league for over 10 years.
The hosts made a fast start to the match and went close to opening the scoring whenJuan Mata's 20-yardfree kick curled just wide of the post.
Arsenal were slow to grow into the game and although they began toshade possession,United looked threatening on the break. Anthony Martial was inches away from getting on the end of a brilliant Rashford cross as the Red Devils looked the more likely to break the deadlock.
35' - Huge claims for an #MUFC penalty after Monreal challenges Valencia but referee Andre Marriner waves it away. #MUNARS
United were then left incensed after Antonio Valencia appeared to be dragged to the floor by Nacho Monreal in the penalty area but the referee rejected the home crowds vociferous appeals.
Mata went close again moments later, but saw his low effort pushed around the post by a diving Petr Cech.
The Gunners were now under pressure and theirkeeper came to the rescue for a second time when hetipped Martial's curling effortover the bar.
Despite their dominance, Mourinho's side were unable to find the goal their play deserved, but went into the interval much the happier team as their opponents had failed to muster a single shot on target.
The second half saw little change in proceedings, as the away side continued to look laborious and disjointed.
United's intensity had eased a littleand althoughthey were seeing most of the ball, they wereunable to create any further chances of note as the match drifted into the final 30 minutes.
The hour mark saw the arrival of Wayne Rooney, who had made headlines for all the wrong reasons before the match after being pictured gatecrashing a wedding whilst intoxicated with alcohol.
The striker's introduction seemed to re-energise the home side and they finally made the breakthrough in the 68th minute, when Ander Herrera's cut-back was smashed in by the unmarked Mata.
GOAL: Manchester United 1-0 Arsenal
Juan Mata has done it. Wenger is losing to Mourinho again.
Live: https://t.co/OY04OjHKdu #MUNARS pic.twitter.com/0OKlOwDgeN
In truth, the goal was well earned by the hosts who had finally made the most of a much improved performance.
Arsene Wenger brought Olivier Giroud off the bench in a bid to wake his players from their slumber but the Frenchman's introduction appeared to have little effect.
Arsenal's passive play made it easy for United to sit behind the ball and defend with ease as Mourinho responded to the match situation by making defensively minded substitutions of his own.
But there would prove to be a late sting in the tail as Giroud bailed the visitors out when he grabbed an equaliser with only minutes to spare.
The striker powered substitute Alex Oxlade-Chamberlain's deep cross past a helpless David De Gea as Arsenal scored with their only effort on target.
Although United pushed for an injury time winner, they were left to curse their luck as Andre Marriner blew the full time whistle, meaning both sides' left Old Trafford with a point.
#MUFCvAFC team news:
Rashford & Martial start for #MUFC
Sanchez starts for #Arsenal, Jenkinson in for Bellerin.
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