Adeyemi, 23, joined Cardiff from Birmingham City last summer, and played 23 games for the Bluebirds last season under Ole Gunnar Solskjaer and then Russell Slade.
However, it now looks like Adeyemi will be on the move again, with the BBC reporting that the midfielder is set to complete a transfer to Leeds United, initially on loan but with an option for a permanent move next summer.
The Whites are now managed by Uwe Rosler, and the German signed Adeyemi during his time as Brentford boss back in 2012, meaning the duo are now poised to reunite at Elland Road.
Having released Rodolph Austin this summer, Leeds needed a new midfielder - and the recent injury to Luke Murphy only exacerbated that concern, with Adeyemi now set to rectify the issue for Rosler.
What will Adeyemi bring to Leeds?
The former Norwich City man is best known for his athleticism. Standing at 6ft 1in tall, Adeyemi is a physical presence, possessing strength and a decent turn of pace in midfield.
Adeyemi is far from a prolific goalscorer from midfield, but he can get forward to make an impact in the final third, whilst he is also known for being a tough tackler too.
The 23-year-old looks to be an ideal replacement for Austin in the Leeds midfield, and with concerns over Murphy, Rosler has moved quickly to snap up a midfielder he knows all about having managed him previously at Brentford.