On every date between now and Christmas, we will bring you a quick quiz on a famous player or players who have worn that number on the back of their shirts for Chelsea.
Today you have questions on no less than five players to test your knowledge, with current defender Andreas Christensen joining his predecessor David Luiz, pass master Cesc Fabregas, the ultimate anchor man Claude Makelele and revolutionary Dutch master Ruud Gullit.
That’s quite some list of number fours, so try our quiz and find out how well you know them. Just like with an advent calendar, you can come back and open a new quiz every day until Christmas Day. Unfortunately we can’t give you all a chocolate to enjoy with your quiz, but feel free to treat yourself if you score high. Good luck and merry quiz-mas!