INJURY TIMEpublished at 45 mins
Arsenal 1-2 Man Utd
Three minutes added on, there was a lengthy injury break earlier on of course.
Man Utd into FA Cup fifth round
Eighth straight win for Solskjaer as interim manager
Sanchez scores against former club
Result: Bristol City 2-1 Bolton Wanderers
Tom Rostance
Arsenal 1-2 Man Utd
Three minutes added on, there was a lengthy injury break earlier on of course.
Arsenal 1-2 Man Utd
Jermaine Jenas
Former England and Tottenham midfielder on BBC One
Aubameyang just gets himself into a goalscoing position. It was brilliant from Aaron Ramsey with a step-over. Game on. The team talks are totally different now. Much easier on Unai Emery.
Pierre-Emerick Aubameyang
Game on!
Aaron Ramsey is the gamebreaker, the linebreaker to run into the box, beat Eric Bailly and put it right across goal.
Alexandre Lacazette stretches but can't make proper contact, he does touch it on to Pierre-Emerick Aubameyang though and the Gabon goal getter sweeps it in from about three yards out.
Onside? Yep.
#bbcfacup or text 81111 (UK only)
Ole knows the weaknesses of this United team but what he has done so well is to play to their strengths. Counterattacking football at its best
Tim
Carl: Just give him the job now. Done deal.
Arsenal 0-2 Man Utd
Jermaine Jenas
Former England and Tottenham midfielder on BBC One
Even though Arsenal have had a lot of possession, United look solid and organised. Unai Emery needs to have a good think on how to break down that defence.
Arsenal 0-2 Man Utd
Arsenal are almost caught out on the break again but Alexandre Lacazette hustles back well to clear his lines. Aaron Ramsey then has a shot deflected wide!
Bristol City 2-1 Bolton
It was a very positive start for Bolton, but Lee Johnson's Bristol City are firmly on top now at Ashton Gate as they seek a first fifth round spot since 2000-01.
Arsenal 0-2 Man Utd
Romelu Lukaku has been playing on the right wing - to devastating effect so far - that one touch just outside the box in the centre was his first assist.
Arsenal 0-2 Man Utd
Manchester United have had three shots, two were on target, two were goals. Clinical.
Bristol City 2-1 Bolton
A nasty one for Nathan Baker sees a long stoppage just before half-time at Ashton Gate.
The Bristol City defender takes a knock to the head in a 50-50 collision but he's back on his feet now.
Four minutes of first half stoppage time to play.
Phil McNulty
BBC Sport chief football writer at Emirates Stadium
Ruthless from Manchester United and they are in total control. Arsenal are stunned.
Composed finishes from Sanchez and Lingard but what about Lukaku the creator? Great work on both occasions.
United's travelling fans, as you might expect, are jubilant.
#bbcfacup or text 81111 (UK only)
Matt: Solskjaer doing a great job of showing he’s tactically up there with the best of them. He’s not just here for the ‘feels’
Simon: Lukaku is having a great game. I hope he pops up with a goal
Lee: Anyone questioning the inclusion of Lukaku and Sanchez now?
Arsenal 0-2 Man Utd
Arsenal fans and players alike have been stunned by that two-goal burst. Can the Gunners find a way back into this?
Arsenal 0-2 Man Utd
Ole Gunnar Solskjaer - the manager Manchester United never knew they needed?
Arsenal 0-2 Man Utd
John O'Shea
Former Manchester United defender
The balance, speed and then the composure from Alexis Sanchez for the opener. He's probably feeling fully fit again and that finish tells you everything you need to know. A great ball from Lukaku too, which people don't give him a lot of credit for.
Arsenal 0-2 Man Utd
Jermaine Jenas
Former England and Tottenham midfielder on BBC One
That's the game plan right there. They know Sead Kolasinac is much better going forward than defending, that's why Romelu Lukaku is on the right. Two great assists and that's as cool as you get from Jesse Lingard. I'm sure they've been working on that all week.
Jesse Lingard
Ole Gunnar Solskjaer's dream start continues!
Romelu Lukaku has turned into a playmaker as he has a second great asisst in a matter of moments! Arsenal are caught on the break just like Spurs were last week as the visitors free Lukaku down the right, he picks out Jesse Lingard and the England man is super composed to just pass it into the corner from about 12 yards.
Arsenal 0-1 Man Utd
Jermaine Jenas
Former England and Tottenham midfielder on BBC One
This goal is all about Romelu Lukaku. What a ball. The composure of Alexis Sanchez to take it round Petr Cech and keep his cool. The ball from Lukaku sucked everyone in, they all expected him to shoot.
What a finish.
He's hardly been in the game and he's struck the first blow. I'm not sure United deserve the lead on the state of play. But the moment of quality from Lukaku has made the difference.
Alexis Sanchez
If truth be told Alexis Sanchez has had a shocking opening half hour, every time he's had the ball he's lost it but give him a chance and he can still do the business!
It's a really good goal.
Romelu Lukaku gets the ball on the edge of the area, swings to shoot left footed but as four Arsenal men charge him down he plays a deft pass into Sanchez's run. The Chilean can dance around Petr Cech and then, from a tight angle, he sweeps into the corner.
Brilliantly taken.