The Ghana left-back is joining Greek side PAOK, having barely featured for the Blues since his 2015 signing.
He initially signed on a five-year deal from Augsburg, but after 23 appearances in the 2015/16 season, he spent the remainder of his time as a Chelsea employee on loan.
He joined the Blues for a fee of £14million rising to £22m, meaning the Blues could have ended up paying just shy of £1m for each of his appearances.
Baba Rahman's only season featuring for Chelsea was a rare trophyless campaign for the west London side with his last match a 1-1 draw with Liverpool in May 2016.
They finished 10th in the Premier League in a campaign that saw Jose Mourinho sacked and replaced by Guus Hiddink.
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Since then he's spent three seasons with Schalke, before going to Mallorca, PAOK, and then Reading for two seasons.
He was part of the Royals side that were relegated to League One last season, but will now be on his way to Greece.
Perhaps the most curious part of Baba Rahman's time as a Blue was the fact he signed a contract extension in 2021, committing his future to Chelsea until 2024, but he has now left a year early.
Despite a nomadic career, Baba Rahman has been a constant for his national side Ghana, earning 51 caps and making the final of the Africa Cup of Nations in 2015.