They play Real Madrid at 8pm.
Real Madrid manager Carlo Ancelotti says he's 'sad' to see Chelsea struggle this season.
The Italian goes up against his former club tonight in the quarter-finals of the Champions League.
Ancelotti won a Premier League title with Chelsea in 2010, but the Londoners are currently in the bottom half of the table.
He says he remains a supporter of the club.
Kick off for their first leg encounter at the Bernabeu is at 8pm.
At the same time in Italy, AC Milan take on Serie A leaders Napoli.

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