It may not have ended well for the Spanish boss, yet Karanka did guide Boro back to the Premier League after seven years out of the top flight.
We look back at Karanka’s best 13 games in charge of the Teessiders – scroll down and flick through our picture gallery to see the full list:
5. Middlesbrough 3 Leeds United 0 (9th) - 27/09/15
Boro laid down a marker after sweeping Leeds aside at the Riverside in September. The visitors were put on the back foot after just three minutes when David Nugent opened the scoring. Photo: Richard Sellers
6. Middlesbrough 1 Hull City 0 (8th) - 18/03/16
A huge game between two promotion contenders was decided in stoppage-time when Nugent headed home Albert Adomah's cross. It was the first game since Karanka's non appearance at Charlton. Photo: Richard Sellers
7. Middlesbrough 4 Ipswich 1 (7th) 14/03/15
A Bamford double at the Riverside saw Boro keep pace with the automatic promotion contenders after a convincing win. Photo: Richard Sellers
8. Sunderland 1 Middlesbrough 2 (6th) - 21/08/16
Karanka claimed his first Premier League win after a 2-1 victory over North East neighbours Sunderland. Christian Stuani stole the show with a memorable brace at the Stadium of Light. Photo: Stu Forster