Xavi’s progression through the teams earned him a first-team appearance in a Copa Catalunya match against Lleida on 5 May 1998 and he scored his first goal on 18 August 1998 in the Super Cup final against Mallorca. His debut in La Liga came against Valencia on 3 October 1998 in a 3–1 victory for Barcelona. Initially featuring intermittently both for the reserve and senior teams, Xavi scored the only goal in a 1–0 victory over Real Valladolid when Barcelona were in tenth position in the league. Sustained impressive performances meant that he became a key member of Louis van Gaal’s title-winning team, finishing his debut season with 26 matches played and being named 1999 La Liga Breakthrough Player of the Year. Xavi became Barcelona’s principal playmaker after an injury to Pep Guardiola in the 1999–2000 season.

In these years, Barcelona was on the verge of bankruptcy and struggling to keep its place in La Liga’s elite. Playing midfield, but in a more defensive role, Xavi made 20 assists and scored 7 goals in those two seasons. On 16 March 2002, he scored his first goal in El Clásico against Real Madrid.

Xavi was named the vice-captain in the 2004–05 season, in which he helped Barcelona win La Liga and the 2004 Supercopa de España. He was named La Liga Spanish Player of the Year in 2005.

In the 2005–06 season, Xavi tore the ligaments in his left knee in training; he was out of action for four months but returned in April and was on the substitutes bench for Barcelona’s win in the 2006 Champions League final against Arsenal. He also won La Liga and the Supercopa de España again.

He was a main part of Barcelona’s treble and scored the fourth goal in the 4–1 win in the 2009 Copa del Rey Final against Athletic Bilbao, with a free kick. In La Liga, one of his most significant games was the 6–2 Clásico victory over Real Madrid on 2 May; he assisted four goals – once to Carles Puyol, once to Thierry Henry and twice to Lionel Messi.

In the 2009–10 season, Xavi again topped the assists table and provided both the assists in Barcelona’s 2–0 victory against Real Madrid at the Santiago Bernabéu Stadium. Barcelona won the Liga title with a record 99 points, and Xavi was acclaimed Barcelona’s second-best player in a season-long vote. On 3 June 2010, Madrid-based newspaper Marca awarded him third place in the annual Trofeo Alfredo di Stéfano award for the best player in La Liga, behind Lionel Messi and Cristiano Ronaldo.

On 9 June 2010, Xavi signed a new four-year contract with the club, which could be automatically renewed up to 30 June 2016 based on number of games played. On 29 November, he scored his third goal against arch-rivals Real Madrid in a 5–0 home win. On 18 December, he scored another goal against Espanyol in a 1–5 win. In the Champions League, Xavi scored a valuable goal with an assist from David Villa in a home win against Arsenal, that saw Barcelona progress to the quarter-finals.

On 2 January 2011, in a league match against Levante, Xavi made his 549th appearance for the club in all competitions, matching the record held by Migueli. Xavi later became the player with the most appearances for Barcelona of all time. On 28 May, Xavi was imperious in the 2011 UEFA Champions League Final at Wembley Stadium in London as Barcelona defeated Manchester United in the showpiece for the second time in three seasons, winning 3–1.

On 18 December, in the 2011 FIFA Club World Cup Final in Yokohama, Barcelona won 4–0 against Brazilian side Santos as Xavi scored a goal and made an assist to Lionel Messi. After the ball was slightly behind him, Xavi brought the ball down with a cocked leg, effectively using his ankle to control it, before slipping a pass through to Messi, who scored the first goal.

On 18 December 2012, Barcelona renewed Xavi’s contract, extending it until 30 June 2016. He scored a goal against Real Madrid in a 3–2 win for Barcelona. Xavi was named in the FIFA World XI, along with teammates Iniesta, Messi and Dani Alves. Barcelona had virtually secured their La Liga title by the start of 2013, eventually equalling Real Madrid’s 100-point record of the previous season.

Since July 2013, Xavi has been married to Nuria Cunillera. Their daughter, Asia, was born on 3 January 2016. On 25 July 2020, Xavi confirmed he tested positive for COVID-19. As of 29 July 2020, it has been confirmed that he has recovered from the virus.

On 16 January 2014, Xavi made his 700th appearance for the first team against Getafe in the Copa del Rey. For the first time in five years, Barcelona ended the season without a major trophy; they were defeated in the Copa del Rey final by Real Madrid with Gareth Bale scoring a late winner, and lost the league in the last game to Atlético Madrid.

In June 2014, it was announced that Xavi would be leaving the club. On 22 July, however, after talks with newly appointed manager and former teammate Luis Enrique, Xavi decided to stay at Camp Nou for one more season. He was also appointed as club captain. On 25 April 2015, Xavi made his 500th La Liga appearance, becoming the eighth player in history to do so. On 4 June, a farewell event was held at Barcelona for Xavi with players, managers, friends and family paying tribute to him.

On 5 August 2014, following the 2014 World Cup where Spain were eliminated at the group stage, Xavi announced his retirement from international football, having made 133 appearances in a 14-year period. Spain’s World Cup-winning manager Vicente del Bosque paid tribute, stating that Xavi was “a key part of the team’s style of play” and “he was more important to us than even the manager”, also adding, “We will miss him both on and off the pitch. He is a player who we hold in great esteem both personally and as a player. He is and always will be a person and a player who is greatly valued by the federation, the coaching staff and by myself.”

In November 2014, Xavi appeared in FIFA’s “11 against Ebola” campaign with a selection of top football players from around the world, including Cristiano Ronaldo, Neymar, Gareth Bale and Didier Drogba. Under the slogan “Together, we can beat Ebola”, FIFA’s campaign was done in conjunction with the Confederation of African Football (CAF) and health experts, with the players holding up 11 messages to raise awareness of the disease and ways to combat it.

On 6 June 2015, Xavi came on as a 78th-minute substitute for Andrés Iniesta to make his final appearance for Barcelona during the Champions League final, as the club won its fifth European Cup, beating Juventus at Berlin’s Olympiastadion. Xavi, as club captain, lifted the trophy. This made Barcelona the first club in history to win the treble of domestic league, domestic cup and European Cup twice. Xavi, Iniesta, Messi, Gerard Piqué, Pedro, Sergio Busquets and Dani Alves were part of both treble-winning teams.

On 21 May 2015, Xavi announced that he would join Qatari club Al Sadd at the end of the 2014–15 season on a three-year contract. According to his agent, the deal would involve him becoming an ambassador for the 2022 FIFA World Cup in the country, and also start his coaching qualifications. He made his debut for Al-Sadd in a 4–0 win over Mesaimeer on 13 September 2015, assisting in the team’s first goal. In the following match, he scored his first goal for the club in a 2–2 draw with Umm Salal. Al Sadd ended the league campaign in third position putting them in a place for the next season’s AFC Champions League. Xavi scored three goals during the season. In the Champions League, Al Sadd were knocked out from the qualifying rounds by Emirati side Al Jazira on penalties; Xavi missed his spot kick.

Xavi won his first trophy with Al Sadd following a 2–1 victory over El Jaish in the Qatar Cup final on 29 April 2017. On 10 November 2017, Xavi said that he would retire when his contract with Al Sadd expired at the end of the 2017–18 season, and would later pursue a coaching career. However, he postponed these plans and signed a two-year contract extension on 24 May 2018.

In October 2018, Al Sadd reached the 2018 AFC Champions League semi-finals of the tournament with Xavi as captain but were eliminated 2–1 by Persepolis.

On 2 May 2019, Xavi announced that he would be retiring from professional football at the end of the season. On 20 May 2019, Xavi played the final match of his career, a 2–0 defeat to Persepolis in Tehran, which was Al Sadd’s final AFC Champions League group match; before the match, he stated that he would like to remain in Qatar after his retirement, and that he would look to begin a coaching career, commenting: “The idea is to start as a coach in Qatar, to test myself and get some experience.”

On 28 May 2019 it was announced that Xavi would take over as manager of Al-Sadd on a two-year contract. Xavi helped the club reach the semi-finals of the AFC Champions League, where they were eliminated by Al-Hilal FC 6–5 on aggregate. In the league, the club finished as third. In the 2019/2020, Xavi led his team to win three domestic tournaments. At the 2020 AFC Champions League, Al Sadd reached the semi-finals but were eliminated 0–1 by Persepolis.