Head coach Aitor Karanka says his future at Middlesbrough was never in doubt after signing a four-year contract with the Championship side.
He had one year left on his initial contract.
"It's not about money or years, it's an amazing relationship, I'm at the best club for me," Karanka told BBC Tees.
"After the play-off final when some rumours about other clubs were around, the chairman [Steve Gibson] knows I never considered them.
"The relationship with Steve and the people and the club means more than paper."
The former Real Madrid assistant has won 44 of 87 games in charge of the Riverside club.