The Gunners had a difficult start to the Premier League season under Arsene Wenger’s replacement Unai Emery.
Arsenal lost to defending Premier League champions Manchester City and FA Cup holders Chelsea FC in their opening two fixtures.
The north London side have responded with four successive Premier League victories over Newcastle United, Everton, Cardiff City and West Ham United.
Arsenal are in sixth spot in the table and a point behind Watford, who occupy the final Champions League qualification spot.
Watford have made an impressive start to the Premier League season after victories over Brighton, Crystal Palace, Burnley and Tottenham.
Former Arsenal playmaker Merson can’t see past an Arsenal victory at the Emirates Stadium on Saturday evening.
“Watford will be disappointed after the Carabao Cup exit to Tottenham, but they’ve done well so far this season,” Merson told Sky Sports.
“But Arsenal are rolling and I can only see them getting a win here.”
Arsenal finished in sixth spot in the Premier League last term to miss out on a place in the Champions League in successive seasons.
The Gunners appointed Emery as Wenger’s successor in the summer after 22 seasons under the Frenchman’s management.
Arsenal signed five new players in the summer transfer window to bolster Emery’s squad ahead of the new Premier League campaign.
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