Frank Lampard has said that he expects Chelsea to face a "difficult" time when they play Fulham this weekend.
The league leaders travel to their local rivals, who sit bottom in the Premier League table, tomorrow.
The club's record goal scorer told the team's website: "If you sit off or relax for a game you'll lose at this stage of the season. If you look at Fulham, they're fighting for their lives so if we're not at it they'll get a result.
"It's a local derby and the fact they're struggling might make it more difficult for us because they're so desperate for points, maybe it would be better if they were in mid-table and cruising.
"What we need to do is prepare, we can't moan, we've got a fantastic, big squad, fit young players and we have to get ready and go again."
Chelsea beat Fulham 2-0 when the sides met at Stamford Bridge earlier in the season.