We had to settle for a draw in a scrappy, disjointed match at Old Trafford, despite twice taking the lead.
The four goals summed up the match, which although was lacking in in quality, was not short on drama.
But there will be a huge sense of frustration that we twice threw away leads, conceding within moments of taking the lead on each occasion.
After a fairly uneventful opening 25 minutes, we broke the deadlock when David De Gea failed to hold a Shkodran Mustafi header from a corner. The keeper could only palm the ball up and over the line – the goal was awarded with the aid of the goal-line technology, with Ander Herrera failing to make his clearance in time.
Our lead lasted barely five minutes though. Bernd Leno did superbly to keep out a free-kick from Marcos Rojo but Herrera kept the loose ball alive, cut it back to the centre and Anthony Martial tucked home the equaliser.
To say the rest of the half was scrappy would be an understatement. First Rob Holding was forced off with a knee injury, Rojo was then fortunate not to see red for a late lunge on Matteo Guendouzi. He was only booked by Andre Marriner - one of five yellow cards in a crazy five-minute spell to end the half.
The second half continued in a fragmented fashion, until substitute Alexandre Lacazette gave us the lead, and it was a goal befitting the haphazard nature of the game. Rojo gave the ball away in midfield, we sprang forward, released Lacazette who was tackled by Rojo when through on goal, but the ball ricocheted into the net.
Once again our joy was shortlived. From the kick off United launched the ball forward, Read Kolasinac failed to get enough on the backpass and Jesse Lingard pounced to level.
There were 74 seconds between the goals, Unai Emery was rightfully livid on the touchline.
We kept coming though. Pierre-Emerick Aubameyang was denied from close range, then saw a curling effort well saved by De Gea, while Henrikh Mkhitaryan also shot just wide at the near post.
Mkhitaryan had the ball in the net late on, but was ruled offside, as we extended our unbeaten run to 20 games.
HOW IT HAPPENED
WHAT IT MEANS
It's another quick turnaround for the weekend, as we take on Huddersfield Town at Emirates Stadium this Saturday.
Copyright 2019 The Arsenal Football Club plc. Permission to use quotations from this article is granted subject to appropriate credit being given to www.arsenal.com as the source.