Neither did former Liverpool midfielder Graeme Souness, who slammed Arsenal's performance as "totally unacceptable."
The defeat leaves Arsenal five points back from Premier League leaders Leicester City with 11 games of the season remaining, and Henry said it was not a performance befitting of league champions, per Sky Sports (via Jack Lang in the Mirror): "That wasn't the performance of a team that wanted to be champions. The only thing that is good is they are still in the title race. Arsenal had to do a bit more than that and they didn't. How am I going to feel confident as an Arsenal fan now when they go White Hart Lane or Goodison Park?"
Arsene Wenger's side came up against a severely understrength United side—their squad has been ravaged by injury—but they were 2-0 down inside 32 minutes after a double from 18-year-old striker Marcus Rashford.
Danny Welbeck got Arsenal back in the game with a goal five minutes from half time, bur Ander Herrera restored the hosts' two-goal cushion in the 65th minute.
Mesut Ozil then found the net four minutes later, but a late siege of United's goal was never forthcoming from Arsenal, and Louis van Gaal's side looked fairly comfortable in seeing out an important victory, per football writer Miguel Delaney:
Miguel Delaney @MiguelDelaney
Where exactly was the Arsenal siege last 10? Unreal. Both testament to United and awful for Wenger that all life in this came from kids.2016-2-28 15:58:23
Souness gave a damning assessment of Arsenal's limp performance, per Sky Sports (via Lang): "Arsene Wenger must be tearing his hair out. There’s a word I want to use, but I can’t, which describes a lack of something real players have. And these Arsenal players lack it in abundance, they just don’t have it, none. That today was totally unacceptable."
None of Arsenal's players came to the fore and tried to inspire their side to a victory. Alexis Sanchez was again largely ineffective, and he continues to struggle following his return from injury, per Bleacher Report's Dean Jones:
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Arsenal's defence was also very poor, with Rashford able to ghost into the box and head home for his second and Herrera not picked up on the edge of the box for the third, per MailOnline's Lee Clayton:
Lee Clayton @LeeClayton_
Arsenal are a shambles at the back. No leadership, no communication. That is not the defence of champions.2016-2-28 15:19:43
The two north London sides face off at White Hart Lane on Saturday after a round of midweek action, and Arsenal could well drop out of the title race for good if they lose to their bitter local rivals.
Wenger's side will need a significantly improved performance against Spurs if they are to claim a vital win, but it will be a very tough task given how consistently good Mauricio Pochettino's team have been this season.
Arsenal's title hopes are hanging by a thread following the United defeat, and the Gunners need to show their mettle if they are to stay in the hunt for a first top-flight win since 2004.