Xavi: the best coach in the world - but could Guardiola be put on the sidelines? © EuroFootball.com

Saugas Xavi claims that Pep Guardiola, who has made "fundamental changes in football", is the best coach in the world.

In the summer of 2008, replacing Frank Rijkaard at the helm of the Catalan team, the Spaniard won the country's championship three times, the Champions League twice, and adorned himself with other prestigious trophies.

In an interview with "Sport," Xavi said: "I think Guardiola is the best in the world. I have no doubts about that. He fundamentally changed football and gave this club everything it needs.

No one questions Guardiola's decisions, even when he benched Sergio Busquets in the European Super Cup match. Every footballer will have moments when they won't play. Even Lionel Messi."

And he added: "Those who think they are untouchable won't go far with Pep. Past achievements mean nothing. Everyone is equal and must prove they deserve to play."