The north London side suffered a surprise setback when they were beaten by the Hornets at The Emirates in the Premier League to dent their title hopes.
Wenger’s men must now dust themselves down as they prepare for their crunch Premier League clash against Chelsea at Stamford Bridge on Saturday afternoon.
Arsenal are now nine points behind the leaders and will need to win the game if they want to keep their fading title hopes alive.
Asked whether his team could struggle to deal with Chelsea’s physical power on Saturday afternoon, Wenger told his post-match news conference on Tuesday night: “No, I don’t think we have a physical power problem.
“I think we were not mentally ready to deal with the duels that we usually do.
“You don’t make 47 points in the Premier League after 23 games if you have no physical power. But you have to switch it on at 100 per cent every time in the Premier League, that’s what it is about.”
Arsenal finished second last season and are looking to win the Premier League title for the first time since their famous unbeaten triumph in the 2003-04 campaign.
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