Alexis Sanchez strikes twice as Arsenal humble Manchester United

United were blown away right from the off, and the high line they adopted left them vulnerable on the counter, which Sanchez and co took full advantage of.

Ozil and Sanchez linked up brilliantly for the opener in the sixth minute, with the German's pinpoint cross flicked in at the near post by the Chile forward. Johan Cruyff would have been proud of that finish.

And one minute later, United were undone again, this time Theo Walcott laying on a perfect pass for Ozil to steer home, and send the Emirates into raptures.

The Gunners were three to the good in under 20 minutes, after Sanchez rode the half-hearted challenge of a hapless Matteo Darmian, before rifling an unstoppable strike into the top corner, leaving David de Gea no chance.

United huffed and puffed but that opening 20 minutes of madness settled this encounter, with Petr Cech making several fine saves to preserve the Gunners' clean sheet.

Despite supposedly being in “crisis”, the result sees Arsenal leapfrog United on goal difference, and the Gunners are just two points behind leaders Manchester City. The title race is well and truly on.

6’- GOAL! Arsenal 1-0 Manchester United. What a start for the Gunners. A superb finish from Alexis Sanchez at the near post sends the home fans into raptures. United all over the place!

7’ - GOAL! Arsenal 2-0 Manchester United. What is going on? Theo Walcott cuts the ball back for Mesut Ozil to steer home and double the Gunners' lead in under seven minutes! United all at sea.

19’ - GOAL! Arsenal 3-0 Manchester United. Wow! Three inside 20 minutes. All Sanchez's doing. He skips through the challenge of Darmian on to his right foot, and fires the ball into the top corner. He's on a hat-trick already!

34’ - CHANCE! Should have been four! Wonderful clipped cross from Sanchez picks out Aaron Ramsey, who is unmarked, but he side-foots his volley over from close range.

45’ - SAVE! He has had almost nothing to do, but Cech reacts brilliantly to smother Martial's effort at goal. Great turn by the Frenchman, but Cech was alert to save with his legs.

62’ - SAVE! In search of his first Premier League away goal since this fixture last season, Rooney has an effort at goal, but Cech gets two hands to it and beats the ball to safety.

68’ - SAVE! Cech again to the rescue. Schweinsteiger's touch lets him down when played in, but the Arsenal stopper was out quickly to save at the feet of the German midfielder.

73’ - CHANCE! Good work from Monreal picks out Ozil in space on the edge of the box, but his powerful strike is straight at De Gea.

85’ - CHANCE! Should have been four! Giroud holds back, is picked out ten yards from goal, with the net gaping, but he tamely fires straight at De Gea.

90+2’ - WOODWORK! Oxlade-Chamberlain hits the crossbar after being put through. Was a delightful chip, but just got a little bit too much on it.

Arsenal have ended a run of eight Premier League games without a victory over Manchester United (D3 L5).

Alexis Sanchez has scored more goals in his last two Premier League games (5) than he had in his previous 21 (4).

United have conceded three goals in the first 20 minutes of a PL game for the first time.

Arsenal scored three league goals in a game against United for the first time since November 2001.

Only once in Premier League history have United conceded two goals as quick as they have v Arsenal (2 in 6 mins v Sheff Wed in 1992).

Mesut Ozil has scored and assisted in the same Premier League game for the fourth time.

United set up to press high right from the off, with Bastian Schweinsteiger playing much further forward than he is used to. With a makeshift full-back in Ashley Young getting little protection in front of him, United were torn apart, with Matteo Darmian suffering the same problems on the other flank. Would Morgan Schneiderlin have been perfect to sit right in front of the United backline to slow the Gunners on the counter? Can you really play like United did against Arsenal when they are in the mood?

Alexis Sanchez. Several candidates just missed out with Santi Cazorla orchestrating everything and Mesut Ozil in fine fettle, but Sanchez’s explosiveness around the box was the difference here. His energy is infectious, and in that form, he is simply unstoppable.

ARSENAL: Cech 8, Bellerin 7, Mertesacker 7, Gabriel 6, Monreal 7; Coquelin 7, Cazorla 9; Ramsey 7, Ozil 9, Sanchez 9; Walcott 8… Subs: Gibbs 6, Giroud 6, Oxlade-Chamberlain 6.

MANCHESTER UNITED: De Gea 6, Young 5, Smalling 5, Blind 4, Darmian 3, Carrick 4, Schweinsteiger 4, Mata 5, Rooney 3, Memphis 4, Martial 7… Subs: Valencia 6, Fellaini 6, Wilson 6.