Born in the Basque city of Bilbao, Mendieta made his name as one of the world's finest creative midfielders in a nine-year spell with Valencia. There he won the Copa del Rey, the Spanish Super Cup and the Intertoto Cup, as well as two runners-up medals in the Champions League.
Individual honours would also follow, with the Spanish star twice named the European Midfielder of the Year.
Mendieta subsequently transferred to Lazio for a fee just short of 50m Euros, but struggled to recreate his best form in his single season in Rome and spent the following year back in Spain with Barcelona.
Moves to Atletico Madrid and hometown club Athletic Bilbao were mooted, but Mendi expressed his desire to play in England, joining Boro on loan.
Here he would add another trophy to his already brimming cabinet, the League Cup with Boro in 2004, having a hand in our quickfire first goal in Cardiff and securing his status as a legend of the club.
One of the highlights of his time on Teesside was a virtuoso performance in a 4-1 demolition of Manchester United at the Riverside the same season. He also scored a wonderful solo goal following a quick free-kick against Wolves.
A key figure in the club's forays into Europe over the following two years, Mendieta would sadly miss the latter stages of our run to the final after breaking his foot in training.
His final game before retirement was on Boxing Day 2006, against Everton.