The son of another famous drummer, Starkey has actually been working with the band since 1996.By Gil Kaufman Zak Starkey performs during the Super Bowl XLIV halftime show Photo: Jeff Kravitz/ FilmMagic Every classic-rock fan knows the titanic twosome that fronts the Who: singer Roger Daltrey and windmilling guitarist Pete Townshend. But as the only two original members left of the iconic British rock band, the duo front a group of backup players who are decidedly more anonymous than late madman drummer Keith Moon and steady-on bassist John Entwistle, who died in 2002 on the eve of one of the band's seemingly endless final tours. One of the sidemen that stood out for many football fans watching the Super Bowl halftime extravaganza on Sunday was splashy drummer Zak Starkey, who kept the beat on a medley of the band's most beloved hits: "Pinball Wizard," "Baba O'Riley," "Who Are You?," "See Me, Feel Me" and "Won't Get Fooled Again." Though at 44 a relative youngster compared to Townshend (64) and Daltrey (65), Starkey is actually a nearly 15-year veteran of the touring version of the Who and a well-regarded rock sideman.