Born in Logroño, La Rioja, José Mari was trained in the youth system of CA Osasuna and began his senior career with the reserves in Segunda División B, his first match taking place towards the end of 1988–89.
He spent another two seasons at that level, but also made his La Liga debut for the first team under manager Pedro María Zabalza, coming on as a late substitute in a 3–0 home win against Real Betis just prior to his 20th birthday.
At the end of the campaign he had started four league games and appeared from the bench in another four, and also made his European bow on 22 October 1991 when he played the last eight minutes in place of Miguel Sola in a 0–0 home draw against VfB Stuttgart.
[4] José Mari initially remained in Pamplona and played in Segunda División until January 1995, when he was signed by FC Barcelona for 150 million pesetas (equivalent to around GB£720,000 at the time) and returned to the top level on a three-year contract.
He was one of three Barcelona players transferred in discounted deals along with Óscar Arpón and former Osasuna teammate Francisco Sánchez Jara, in the wake of Ángel Cuéllar's move in the opposite direction via his buyout clause.
In his first season – at the outset of the Luis Fernández managerial era – José Mari was a regular fixture (33 games, 28 starts), scoring the winning goal on his debut against Rayo Vallecano[8] and netting the equaliser in an eventual 2–1 home victory over his former side Barcelona on 23 November 1996.