Arsenal undo Mourinho's unbeaten streak to set their sights on top four
Mourinho's focus was on the Europa League and Wenger took advantage to claim his first league win over the Portuguese manager, and revive the Gunners' Champions League hopes.
The match looked promising with very much on the line for both teams, and it did not disappoint. It was an exciting start to the game with end-to-end football that attested to each team's intentions.
In the opening minutes, chances arrived at both ends, with the keepers pulling off good saves to deny the deadlock being broken. Possession was also well distributed in the first half as the teams took turns to claim the ball and attack.
De Gea saved shots from Ramsey and Oxlade-Chamberlain, while Cech did well to deny efforts from Martial and Rooney, after Rob Holding gifted the United captain with an opportunity through on goal.
Towards the end of the half, Mourinho's team took a step back to hold a more defensive stance. The Gunners were seeing almost all of the ball, but they could not break down United's deep-sitting defence to get through on De Gea.
It was an all-too-defensive display from the Red Devils in the second half which allowed the hosts to come forward and capitalise in the space of three minutes.
Granit Xhaka took aim from distance and his strike was deflected off Herrera's back to wickedly dip into the top corner, past the fingertips of De Gea. It was a great strike, but the Swiss international was immensely lucky to beat the keeper that way.
The away team were still attempting to respond to going behind when the Gunners got a second. Oxlade-Chamberlain crossed an inviting ball into the six-yard box were Welbeck was waiting to power his header in off the crossbar. The former United man has now scored in each of his last three appearances against the Red Devils.
Jose Mourinho attempted to spur a reaction from his team by introducing attack-minded changes, but the additions of Lingard and Rashford made no difference to the final scoreline.
Arsenal completed a solid performance to bring Manchester United's 25 game unbeaten streak to an end, as well as giving Wenger his first Premier League victory over Mourinho.