Roberto Di Matteo has warned his Chelsea team that Saturday's clash with Wigan at Stamford Bridge is a must-win game.
The Blues will enter into a crucial month which will see them contest the semi-finals of the FA Cup and UEFA Champions League.
Chelsea are currently fifth in the league - five points behind fourth-placed Tottenham - but the stand-in boss is keen to secure Champions League football again next term.
Wigan have won their last two games and are attempting to beat the drop once again after residing in the bottom three for most of the term.
Yet, despite their lowly position, Di Matteo is refusing to take them lightly.
"Tomorrow against Wigan, I think will probably prove one of the most difficult games for us," said Di Matteo.
"They are in good form. They always seem to find good form towards the end of the season.
"We have to win, basically. We cannot slip up."