Manchester United put on another defensive disasterclass as they lost 3-1 away to Arsenal to lose further ground in the race for the top four.
It was the case of different players, same story for the visitors as they fell behind to another early goal when Raphael Varane and Alex Telles made a mess with a clearance and Nuno Tavares netted for his first goal for the club.
Unlike the lifeless performances against Everton and Liverpool recently, United responded well to going behind and carved out the better chances with Diogo Dalot rattling the woodwork from distance and Bruno Fernandes' shooting boots letting him down again.
But the defensive frailties continued with Eddie Nketiah netting from close range after United's defence stopped thinking it was offside. After a VAR review, referee Craig Pawson disallowed the goal but awarded a penalty to the Gunners for a foul by Telles just before Nketiah scored which Bukayo Saka coolly converted.
Ralf Rangnick's side reduced the deficit just two minutes later when Nemanja Matic's pinpoint cross was smartly tucked away by the returning Cristiano Ronaldo for his 100th Premier League goal.
The Gunners began the second half with more spark, but it was Ronaldo carrying the visitors again, and he had a goal ruled out for offside.
The turning point came when Tavares was penalised for a handball following a corner to concede a penalty. The out-of-form Bruno Fernandes stepped up and his spot kick hit the post.
Fernandes' poor game continued as he mis-controlled the ball near his box 20 minutes from time. It fell to Granit Xhaka, who unleashed a brilliant shot past David De Gea from distance.
The result sees Mikel Arteta's side move fourth, six points ahead of sixth-placed United, and the Gunners have a game in hand.
It was a defensive showing that may have left the incoming United manager hiding behind the sofa and writing 'need four new defenders' at the top of his shopping list.
Harry Maguire and Aaron Wan-Bissaka were on the bench, Luke Shaw is injured, yet nothing improved.
Alex Telles and Diogo Dalot never look comfortable with the concept of man marking and have not made a case for being at the club next season with their performances.
Raphael Varane's season has been dogged by injury while Victor Lindelof's five years at United has been solid at best.
Other concerns for ten Haag are the performances of Fernandes in games against the other top four contenders and the need for a reliable striker next season to avoid the continued reliance on Ronaldo to dig them out of trouble.
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MAN OF THE MATCH
Bukayo Saka (Arsenal): In a strong team performance from Arteta's side, Saka was a constant threat and gave Dalot a torrid time. He also coolly converted his penalty.
ARSENAL: Ramsdale 6, Cedric Soares 5, White 5, Gabriel 6, Tavares 6, Elneny 6, Xhaka 7, Saka 8, Odegaard 6, Smith Rowe 4, Nketiah 7. Subs: Martinelli n/a, Holding n/a, Tomiyasu n/a.
MANCHESTER UNITED: De Gea 6, Dalot 4, Lindelof 6, Varane 4, Telles 3, Matic 6, McTominay 5, Sancho 5, Fernandes 2, Elanga 5, Ronaldo 8...Subs: Rashford n/a, Lingard n/a, Mata n/a.
Les joueurs d'Arsenal, tombeurs de Manchester United, sont en pleine forme
Image credit: Getty Images
3' - GOAL FOR ARSENAL! Tavares tucks in the rebound after a brilliant De Gea save to keep out a shot from Saka.
24' - WOODWORK! Dalot from distance rattles the bar with a cracker of an effort.
27'- DISALLOWED GOAL FOR ARSENAL! Nketiah bundles the ball in from close range. United thought it was offside and had stopped. VAR saus it was offside but awards a penalty.
32' - ARSENAL SCORE THE PENALTY! Saka sends De Gea the wrong way to double his side's lead. What a pasage of play!
34' - GOAL FOR UNITED! Sancho does well, tees up Matic whose cross finds Ronaldo who tucks it in first time.
57' - UNITED MISS A PENALTY! Tavares is penalised for a handball following a corner. Fernandes steps up, does a skip and hits the post. Oh dear.
70' - GOAL FOR ARSENAL! Saka claiming handball after his cross is blocked. Xhaka then lashes in a brilliant long-ranger pase De Gea, what a strike.
Since the 2003-04 season, Ronaldo is one of only four players to score 100+ goals in two of Europe's big-five leagues (LaLiga, Premier League), along with Edinson Cavani (Ligue 1, Serie A), Gonzalo Higuaín (LaLiga, Serie A) and Zlatan Ibrahimovic (Ligue 1, Serie A).