It was Monreal who scored a fine goal (only his second) after some excellent interplay between Ozil and The Ox. Danny Welbeck's first touches were atrocious in the first half, unable to control any balls when he received them. However, he worked hard tirelessly and put pressure on the home side by pressing high up on the pitch. He capitalised on Antonio Valencia's error and took his chance brilliantly. Wenger provided a chance for him to show what he was capable of if he was given chances to play in his preferred position.
When Welbz was taken off in the 74th minute, he was relatively well received by the whole audience, despite some jeers from a section of Man united fans. There was a question after the match as to whether he was right to celebrate his goal against his former club where he spent so many years. However, it is wrong to question his loyalty. After all, it was his old club and its new manager that have decided that he was not up to its required level. All he wanted to do was to prove that decision wrong and he has every right to show his delight for what he had just done.
Another major talking point of this game was officiating. Michael Oliver earned plaudits for his brave decisions from the broader base of football fans. He never surrender himself to the intimidation of the crowding Man U players or the home crowd and demonstrated his uncompromising attitude towards divers. Initially, we thought he was just like other referees in charge at Old Trafford in the past, when he showed a yellow card for Hector Bellerin's seemingly innocuous foul within the first 3 minute. On the other hand, Marouane Felleini escaped a yellow card for 58 minutes after 5 or 6 potentially bookable offences. Some argue that Arsenal had a genuine penalty claim when Welbz was tripped in the box, but we weren't surprised when the referee simply waved it off as we knew it just would not happen at Old Trafford against the home side. We feared the worst when Michael Oliver pulled a yellow card out of his pocket when Bellerin's challenge was deemed illegal. Fortunately, the young Spaniard remained on the pitch until Wenger decided not to chance on his borrowed life any longer and replaced him with Calum Chambers in the 66th minute. We were further impressed when he booked Angel Di Maria for simulation and sent him off within 30 seconds of the incident for a second bookable offence when the Argentinian manhandled the referee. Then, when we heard the home crowd shouting for a penalty, the ref actually booked Adnan Januzaj for diving. Replays showed that it was an unashamed simulation. Michael Oliver's performance this night was pleasantly refreshing, especially considering that so many wrong decisions have been making headlines this season.
The result saw us through to the semi-finals of the FA Cup. This time around, the draw was also kind to us, with Bradford or Reading to face us at Wembley. We know neither of them should be underestimated, especially Bradford who beat us in the Capital One Cup in the penalty shoot-out. However, we know we are going into the game as heavy favourites because of our club ranking and our title credentials as the current holders. But that's more than a month away. We have more urgent issues of cementing our place in the top three and dealing with the second leg of the Champions League against Monaco.
Although he made a couple of fine saves in the first half, he still hasn't eradicated his rash decisions to come out of his area while his two centre-backs were in control of the situation, or his desire to play the ball on his feet when Rooney was lurking.
Made 3 tackles, 1 interceptions and 4 clearances.
Made 2 tackles, 3 interceptions and 7 clearances. For Rooney's goal, the two centre-backs were too far apart, allowing the England striker to run in between them too easily.
Made 3 tackles, 4 interceptions and 4 clearances. Won 7 aerial duels.
Scored his second goal for Arsenal. Took his goal excellently with the side of his left foot.
Bravely battled against Fellaini. Made 4 tackles, 1 interception and 1 clearance.
Unlucky not to get on the scoresheet when his well-taken volley was denied by De Gea's superb save in the second half. Had 3 shots, 2 of which were on target. Made 6 tackles.
Stats-based Whoscored.com's Man of the Match. Provided an assist for Monreal's opener by cutting in from the right flank, jinking his way through defenders to the middle before he slotted a perfect pass into the Spanish left-back's path into the box. It is a shame that he will have to endure another spell on the sidelines after suffering a hamstring injury.
His recent work-rate stats should silence his critics. He was linking Arsenal's midfield and front line, by tracking back, winning the balls and pressing. He was also taking on two Man U defenders to himself in the build-up to Arsenal's opener to make space for his team-mates.
Unlucky not to score when his shot was finger-tip-saved by David De Gea (we thought the Chilean skewed his shot at the first glance). Had 5 shots, 3 of which were on target.
Worked hard and reacted quickly to the opponents' defensive error. Replaced by Giroud in the 74th minute. Had 2 shots, both of which were on target. However, his touches need improving.
Replaced the injured Ox in the 50th minute. He had to take a yellow card to stop Man U's break.
Came off the bench to replace Bellerin in the 66th minute.
Came on in the 74th minute to replace Welbeck.