Instead, their 1-0 defeat means Liverpool will go 11 points clear if they overcome out-of-form Manchester City on Sunday.

Paul Merson has now criticised Mikel Arteta for a “mind-blowing” decision he made in the fixture, which he says “you just can’t do”.

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Arsenal had no response to Jarrod Bowen’s 44th-minute winner, with their front line unable to get the better of a well-drilled West Ham defence.

Arteta opted to name midfielder Mikel Merino up front for the game, following his amazing brace against Leicester City last time out.

However, lightning couldn’t strike twice as Merino, for all his efforts, simply couldn’t make enough of an impact this time round.

Merson could barely believe Arteta actually went with Merino up front from the off, suggesting it was a foolish decision.

“Arsenal were fortunate last week, let’s be honest,” Merson said on Sky Sports.

“At 0-0 they made Leicester look decent. Merino comes on and scores two very good goals.

“It’s a hard position to play, centre forward, there aren’t a lot of them around.

To just throw people up there and expect them to do the magic, for me, is mind-blowing.

“He looked like a fish up a tree. I don’t mean to be disrespectful to him, he’s a holding midfield player.

“You just can’t do that. I worry for Arsenal now.”

Ian Wright commented on how little firepower Arsenal had in the game and said the fans at the Emirates Stadium picked up on this too.

Prior to the match, Chris Sutton said he couldn’t see Merino impressing against West Ham as he did against Leicester.

"Merino did this to a side edging closer to the Championship,” wrote Sutton. “It would be a monumental ask for him to repeat his heroics again and again.

"To hold up the ball from the get-go. To link with the wingers. To do everything else that strikers need to do as well as scoring. Tougher tests await than leaky Leicester.

"I'll happily eat my words if he bags 14 goals between now and the end of the season as a part-timer in that position. That would truly make this a fairytale find."

To his credit, Merino wasn't bad – he led the line quite well, making some intelligent passes and launching into some good forward runs.

However, this simply wasn't the kind of game where Arsenal could get away with a makeshift forward as was the case against the Foxes.