The English side go into the match in Brussels having hammered Edinburgh 45-0 in their opening match of the competition.
"They're a very successful side littered with some very talented players. So we are under no illusions, it's going to be a tough outing," Barritt told the club's official website.
"Going to Brussels is hugely exciting, playing in a different stadium is always something that excites the players, going to Brussels and taking rugby to a new audience is a very exciting venture.
"We are going to have to stick to our guns, apply the same pressure as last week and be even more clinical than last week."
Racing Metro won their first fixture of this year's tournament 22-17 against Munster.