Xavi Alonso arrived at Bayern as a replacement for Toni Kroos, but he immediately impressed Bayern fans with his delicate foot skills and excellent organisational skills. Under Pep Guardiola, then Bayern manager, Alonso ushered in the second spring of his career, maximizing his remaining enthusiasm and becoming one of Bayern's new midfield core and leaders at that time.
Alonso made his debut at hometown club Real Sociedad, where he spent five seasons turning a relegation division into a La Liga powerhouse. Alonso was signed by Liverpool from Real Sociedad for £15 million in 2004 and completed a stunning comeback with a decisive goal for Liverpool in the 2005 Champions League final against AC Milan. In the end, Liverpool defeated AC Milan 6-5 on aggregate through a penalty shootout, and won the Champions League again after 21 years. In the following year, Alonso was still in great form, and helped Liverpool win the FA Cup. Alonso joined Real Madrid in 2009 for a fee of €30 million, during which time he won the 2011 Spanish Copa del Rey and the 2011-12 La Liga title. In the 2013-14 season, Alonso helped Real Madrid win the Copa del Rey and the Champions League, which Alonso won after being crowned again in 2005.
Alonso officially joined Bayern Munich in 2014. In 2014-15, Alonso made 29 appearances in the Bundesliga and became an indispensable player in Bayern's midfield. Alonso has averaged 138 touches per game this season, including 213 touches in Bayern's 2-0 win away to Cologne in the sixth round of the league, setting a new record since statistics were available in the Bundesliga in 1999, and Alonso's long ball completion rate of 70% allows Alonso to dispatch the team's attacking direction from the back. In the following two seasons, Alonso's performances went from strength to strength, and Bayern won the title year after year. Bayern beat Freiburg 4-1 at home in the final round of the 2016-17 Bundesliga season, and this game was also the last game of Alonso's career. During his time at Bayern, Alonso won three Bundesliga titles, one German Cup and one German Super Cup.
Alonso's international career has been smoother than that of his club. Alonso was called up to Spain for the first time in 2003. At Euro 2008, Alonso accompanied the team and eventually helped Spain win the Delaunay Cup. In the 2010 World Cup, Alonso won the first Hercules Cup in the team's history with Spain's 1-0 victory over the Netherlands. In the 2012 European Championship final, Alonso helped the team defeat Italy 4-0 with his outstanding performance to defend the European Championship title. In 2014, Alonso announced his retirement from the Spanish national team, and throughout his national team career, Alonso played a total of 114 games for the Spanish team, scored 16 goals, and helped Spain win three consecutive major tournaments, and was one of the important founders of the Spanish dynasty.