Marseille playmaker Mathieu Valbuena has declared that tomorrow night's Champions League opponents Napoli remain an unknown quantity, while refusing to give up on their chances of qualifying from Group F.
Elie Baup's side have lost both of their games in the competition so far this season, beaten by both Arsenal and Borussia Dortmund.
Valbuena has admitted that earning a place in the knockout stages looks tough for the Ligue 1 giants, but believes that they are capable of producing a response against Napoli.
He told UEFA.com: "Yes. It is a very difficult group, but it's not impossible either. We beat Dortmund in the last game [of the 2011-12 group stage] which allowed us to qualify, along with Arsenal.
"We know these teams very well, especially Arsenal because a lot of French players and they have a French coach.
"The unknown team are Napoli but looking at their recruitment and investment, they're a big team."
Valbuena is approaching his 300th appearance for Marseille, becoming a firm favourite at the Velodrome since signing his first professional contract in 2006.
