Spieth to launch Masters title defence with Casey, DeChambeau

Mar 26, 2016; Austin, TX, USA; Jordan Spieth of the United States misses this putt to lose to Louis Oosthuizen of South Africa on the 16th hole in round four of the World Golf Championship-Dell Match Play at the Austin Country Club. Mandatory Credit: Erich Schlegel-USA TODAY Sports

AUGUSTA, Georgia (Reuters) - Reigning Masters champion and world number two Jordan Spieth has been grouped with fellow American Bryson DeChambeau and England's Paul Casey for Thursday's first round at Augusta National.

Spieth, a double major winner who stormed to a stunning wire-to-wire victory last year by four shots at the age of 21, will tee off at 9:48 a.m. ET (1348 GMT) with U.S. Amateur champion DeChambeau and Casey.