Xavi believes that Barcelona are the best team of the last 20 years, and also claimed that Lionel Messi is the greatest player of all time.The Blaugrana were in scintillating form again last season, winning a third consecutive La Liga title and collecting a second Champions League trophy in three years.The Spain international spoke in an interview with German newspaper Bild, and was asked to comment on where he felt his team would be placed among the all time elite."There have been some great teams in history, Pele's Brazil, [Johan] Cruyff's Ajax, [Arrigo] Sacchi's Milan, but in the past 20 years this Barcelona team is the best," insisted Xavi.He was also asked to give his opinion on his team-mate Messi, who is widely considered to be the best player of his generation."He is the best player of all time - better than Pele, [Diego] Maradona or Cruyff. We have to protect him as he is crucial. Without him we would not be what we are."The 31-year-old then went on to speak about the contrasting styles of Real Madrid and Manchester United, who Barca both beat en route to lifting the Champions League trophy."Madrid were the hardest opponents but not because they played football but because they wanted to destroy the game."I like Manchester United's approach a thousand times better. It would be interesting to see what would happen if Real did play."Source: Goal.com