Spurs have been flying high in the Premier League and head into the game on the back of their 3-1 win over Crystal Palace last weekend.
The north London side have been tipped by many to be potential candidates to win the Premier League title this season, with Mauricio Pochettino’s men currently fourth in the table and five points behind leaders Leicester City.
Former Arsenal man Merson is not expecting there to be an upset when Spurs take on Colchester on Saturday and is tipping the Lilywhites to cruise through to the next round.
Merson told Sky Sports: “This is my nap of the weekend. It’s a lovely ground, lovely pitch, nice dressing rooms, and that’s why these shocks don’t happen any more.
“You look at Ronnie Radford when he scored for Hereford against Newcastle, the pitch was unreal, you don’t get those any more, they are like snooker tables.
“Colchester are struggling, they let in too many goals, while Tottenham are going really well and their squad is quite big.
“I don’t see anything but a Spurs win. There is no point in them drawing with Leicester at home, going to the King Power Stadium and winning and then taking this game lightly. I think they are a cert.”
Pochettino has been tasked with guiding Spurs back into the Champions League after they finished fifth last season under the Argentine coach.
Their next Premier League game is a trip to Norwich on Tuesday night.
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