The star will perform for the tennis champ, bride Brooklyn Decker and their guests

By Charlotte Triggs
Updated April 16, 2009 03:20 PM
Evan Agostini/Getty; Dave Allocca/Startraks

Elton John will perform at tennis star Andy Roddick s wedding to Sports Illustrated swimsuit model Brooklyn Decker this weekend, multiple sources tell PEOPLE.

“He’s supposed to perform and everyone’s really excited,” says a source of the musical superstar, who knows the tennis champ and groom-to-be, 26, through their mutual involvement in charity work.

Two years ago, John, 62, performed at the Andy Roddick Foundation’s Charity Gala. Last year, Roddick led “Team Elton John” in the Advanta WTT Smash Hits charity event, which raised more than $400,000 for the Elton John AIDS Foundation.

Roddick’s wedding to Decker, 21, will also feature several other celebrity guests, including tennis stars Steffi Graf and Andre Agassi, as well as Marty Fish and James Blake. The pals will attend the small ceremony, to be held at Roddick’s Austin, Texas home, and wedding banquet at a nearby country club.

The bride will also have a fashion contingent at the nuptials, with fellow swimsuit model Julie Henderson in attendance.