Rooney was England's top scorer in qualifying for the finals with nine goals from their 10 games, and the 24-year-old has taken his form into the club season, taking on the burden of scoring more goals following Cristiano Ronaldo's departure to Real Madrid.
Rooney's all-round improvement has not gone unnoticed by Beckenbauer, who says England are among the favourites to lift the World Cup in South Africa this summer - along with Spain, Brazil and Argentina.
"Of course, Argentina have Lionel Messi, who along with Rooney is the best player in the world right now.
"They are different players because Messi is so fast and imaginative while Rooney is so strong, but Wayne has made the biggest improvement to his game.
"He has changed the way he plays and has added a maturity to his game. Playing as the front man, he makes it so hard for defenders to mark him and he is able to use the crosses from both wings so well."
Rooney has scored 33 goals for his club this season
Bayern's former manager, Jurgen Klinsmann, has also tipped the Manchester United man as a possible player of the year in Europe.
"So far, Wayne is playing a tremendous season," Klinsmann told Uefa.com. "He's really hungry for goals, and he wants trophies now.
"He looks calm, he looks confident. So if he continues like that, he might get a shot at the European Player of the Year award."
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