Mandanda: Marseille will turn 2015 form around
Marseille were the early pacesetters in France, losing just three of their opening 17 league matches.
Marcelo Bielsa's men have since lost three of the past five, including a disappointing 2-1 reverse at Nice last Friday.
However, goalkeeper Mandanda has no doubt that Marseille - who sit four points behind leaders Lyon - have the talent and character in the squad to rediscover their early-season form.
"We are aware that since the beginning of January things have been a bit harder," he told Marseille's official website.
"We knew it [a dip in form] was coming. All teams have a dip in the season, Lyon and PSG have one too.
"We must be positive and get back on track. I know it will pass and we will get back to our best. Everyone just needs to find their own level."
Marseille host Evian in Ligue 1 on Saturday.