Last Updated: Sunday, 3 September 2006, 19:31 GMT 20:31 UK
Andre Agassi's career in pictures
Pete Sampras was the greatest player of his generation, but he admits he might not have been without a genuine rival.
"Andre made me a better player," said Sampras after beating Agassi in the 2002 US Open final, the last match of his career. "Borg and McEnroe needed each other. I needed Andre. He was the only guy who forced me to add things to my game."
Agassi summed up their rivalry thus: "We're opposite in everything we do. We're two styles going against each other. Every point, something special seems like it can happen. There's been nothing in my career that compares to playing against Pete."