The 30-year-old former West Ham and Aston Villa man insists the Merseysiders must remain wary of their opponents.
He told evertonfc.com: "People will be watching us and expecting a lot from us because we've played so well in the past and that's what we've got to justify.
"There is a lot of confidence among the players now with the results we've had but we definitely won't underestimate Southampton.
"They're fighting for every point, they want to stay in this league and they're a good footballing side.
"But we have enough confidence to go there and say we want to win this game, and we've got every chance to do so."