Merson believes the Blues have got what it takes to knock Barcelona out of the Champions League.
Chelsea will be wary of the threat posed by Barcelona having faltering against them in the past.
Merson reckons the west Londoners can repeat their exploits of 2012 and overcome the La Liga giants though.
“Chelsea have been inconsistent at times this season but if they show the form they have in certain games they can beat Barcelona in the Champions League,” he told Sky Sports.
“If they play like they did against Roma they will be out of the tie before you know it.
“Chelsea just need consistency and they will be a threat to anybody.”
Chelsea welcome Barcelona to Stamford Bridge on February 20, with the return leg following two weeks later.
Next up for Antonio Conte’s men is Saturday’s clash with Southampton (3pm).
Merson has predicted Chelsea will beat Saints 3-0, saying: “I thought Chelsea were brilliant at Huddersfield.
“I know Tottenham won easily there but Manchester United got beaten there and Manchester City didn’t win until late on.
“Chelsea embarrassed Huddersfield and I can’t see anything but another win here.”