The Gunners head into this weekend’s clash on the back of their impressive 3-0 win over Manchester United at Emirates Stadium before the international break.
That win over the Red Devils left Arsene Wenger’s men second in the Premier League table and just two points behind leaders Manchester City.
And former Arsenal man Merson feels that the north London side are on course to secure a comfortable 2-0 win over Watford in their next top-flight test this weekend.
Merson told Sky Sports: “This is a big game for Arsenal. They were terrible against Olympiakos, then a few days later they rip Man Utd apart. It is Arsenal, it’s them all over.
“It will be hard, but I’m going 2-0 to the Gunners. If they want to be genuine title contenders they have to beat Watford in these types of games. There’s no point being brilliant one week and poor the next.
“You’ll get games with Arsenal that are absolutely brilliant, and others where they’re not.
“This is a massive game, especially with Bayern Munich coming up afterwards. Lose this and then lose to Bayern, and confidence is shot again.”
Gunners boss Wenger hinted on Thursday that star man Alexis Sanchez – who scored twice against Manchester United – could be rested for Saturday’s trip after the forward shone while on international duty with Chile.
However, Merson clearly feels that Arsenal will have too much for the newly-promoted side this weekend.
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