In 1998–99, the Catalan's director of football, Lorenzo Serra Ferrer, promoted Santamaría to the club's B-team, which also included Luis García, Carles Puyol and Xavi.

In the following seasons, he switched back and forth between the B and the C-sides, as both squads operated in 4–3–3, and the player scored 11 goals; on 19 May 2000, he made his first-team – and La Liga – debut, playing 45 minutes against Celta de Vigo in the last matchday.

[1] After the following campaign, in which he played exclusively for the reserves, Santamaría begun a series of loans until his June 2005 final release, all in the second division.

[4] Subsequently, he dropped down to division three, with UE Sant Andreu[5] and CD Logroñés;[6] he had a solid individual season with the latter club, but it was nonetheless relegated due to economic issues.

He was the recipient of the tournament's Golden Ball over the likes of Ronaldinho, Gabriel Milito and Sebastian Deisler, in an eventual third-place finish.