Phil Mickelson backs Rory McIlroy to win US Masters - but it might not be this year

Phil Mickelson, left, and Rory McIlroy during practice for the Masters (Matt Slocum/AP)

Phil Mickelson is adamant that Rory McIlroy will win the Masters to complete the career grand slam.

McIlroy needs a victory at Augusta National to join Gene Sarazen, Ben Hogan, Gary Player, Jack Nicklaus and Tiger Woods as the only players to have won all four major championships.