You have 10 minutes - 50 players will flash up. All you have to do is tell us whether they played for Chelsea, Liverpool, both or neither.
Remember to tweet your scores @FourFourTwo, and challenge some friends while you're at it.
Last time these two sides, it was a stunning match. Liverpool ran out 5-3 winners in an absolute thriller, with goals, dugout disagreements and end-to-end action.
Of course, Chelsea won Liverpool the league by beating Manchester City last season. The Blues have faced the Reds four times in the last year - twice in the league, once in the Super Cup and once knocking them out in the FA Cup - so they're getting to know each other very well indeed.
Tomorrow marks another exciting encounter between two sides expected right at the top of the tree come May. For now though, we want you to remember the alumni of both side - and neither! - to tell us whether the half-century of footballers we named played for Jurgen Klopp's club or Frank Lampard's.
Take your time with this one, as there are quite a few names on there that you probably haven't seen for years...
FIFA 21 The 100 best players revealed
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