Spurs head into the clash against the Hornets after having sealed an impressive 3-0 win over Norwich City at White Hart Lane on Boxing Day.
That victory left the north London side in fourth place in the Premier League table and just six points behind surprise leaders Leicester City.
Former Arsenal man Merson is expecting an entertaining game between the Lilywhites and the Hornets – and is backing the home side to take a point from the top-flight clash.
Merson told Sky Sports: “I’m looking forward to this one. It’s an excellent derby game.
“Watford have been brilliant so far this season and I’m expecting a tough game for the Hornets, even after a really good draw at Stamford Bridge.
“It’s going to be close and I think Tottenham, who are coming off an impressive win, have enough to get a point at Vicarage Road. There’s not a lot between the two sides at the moment.”
Mauricio Pochettino has been tasked with guiding Tottenham back into the top four of the Premier League after Spurs finished fifth last season.
The north London side have been in fine form in the Premier League this season and have only lost twice in the top flight.
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