Tariq Lamptey will hope to show former club Chelsea what they are missing as his Brighton side host the Blues in the Premier League on Tuesday.
The England youth wing-back, 21, joined Brighton in January 2020 after making three senior club appearances for the Blues.
Lamptey has impressed since, making 33 appearances for Graham Potter's Seagulls - scoring once and making five assists.
BBC Sport has taken a look at some other players who have been let go by a big club and then delivered against them.
We're giving you three minutes to work out the identity of these 10 players - good luck!
Can you name the players who have impressed against their former clubs?
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