Xavi Hernandez is considered one of the greatest footballers in history and has been instrumental in the development of Barcelona's tactical system. The 5-time Ballon d'Or winner has been the driving force behind the Catalan club's success over the past two decades.

One of Xavi's most notable contributions to Barcelona's tactics is his focus on possession football. He believes that the best way to win games is by controlling the ball for long periods of time and creating opportunities for their attackers. This approach has helped Barcelona to dominate their league and have won numerous domestic and European titles.

Another key aspect of Xavi's tactical system is the use of a 4-3-3 formation. This formation allows the team to control the midfield with three central players who can both defend and attack. The remaining player is often used as a sweeper or defensive midfielder, while the other two positions are filled by wingers who are tasked with providing width and attacking runs down the flanks.

Xavi's tactical system also emphasizes the importance of penetration through the opponent's defense. He encourages his teammates to work together and look for opportunities to create space and play through the lines. This approach has led to many memorable goals and assists from some of the world's top players.

Overall, Xavi's tactical system at Barcelona is a testament to his ability to adapt and evolve with the game. By focusing on possession football, utilizing a 4-3-3 formation, and emphasizing penetration through the defense, he has helped to shape the club into one of the most successful in recent years. His legacy will undoubtedly continue to inspire future generations of coaches and players.