The Gunners suffered a significant blow to their Premier League title hopes on Sunday as they were beaten 3-2 by Manchester United at Old Trafford.
That result left Wenger’s men in third place in the table, five points behind Leicester and three adrift of Tottenham heading into the final 11 games of the season.
Arsenal must now dust themselves down after the disappointment of their loss at Old Trafford as they prepare to welcome Swansea City to Emirates Stadium on Wednesday night.
And Merson did not hold back in his assessment of Wenger’s situation at Arsenal following their latest defeat.
Speaking on Sky Sports News HQ, Merson said: “If Man City don’t win the league and Tottenham or Leicester do then Arsene Wenger has to go.
“If you’re sitting there telling those fans – loyal Arsenal fans – that they don’t need any new players at the start of the season and then you don’t win the league in front of Leicester or Tottenham then I don’t see how you can justify it.
“If Man City win the league he can turn around and say ‘they’ve got all the money in the world and can go and buy whoever they want, so would whoever I bought have made much difference?’
“But if Leicester or Tottenham win the league after he said they didn’t need any players then I don’t see how he can keep his job.”
Arsenal host Swansea on Wednesday night before turning their attentions towards their crunch north London derby clash with Tottenham Hotspur at White Hart Lane on Saturday.
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