The positive test was first reported by ESPN.
If Braun’s appeal is denied, the Milwaukee Brewers star would be subject to a 50-game suspension.
Braun tested positive for elevated testosterone, ESPN said, adding that a later test determined the testosterone was synthetic.
If suspended, Braun would be eligible to return for Milwaukee’s May 31 game at the Los Angeles Dodgers, barring any postponements.
“There are highly unusual circumstances surrounding this case which will support Ryan’s complete innocence and demonstrate that there was absolutely no intentional violation of the program,” Braun’s representatives said in a statement.
ANGELS: Albert Pujols and left-hander C.J. Wilson made the first public appearances with their new team on Saturday at a raucous pep rally at Angel Stadium.
Thousands of fans showed up to celebrate the Angels’ audacious signing of two elite free agents in their primes for a combined $331.5 million.
Pujols says his decision to leave St. Louis after 11 seasons was gut-wrenching, but Angels owner Arte Moreno’s commitment to charity work and the Angels’ family atmosphere swayed him.
CARDINALS: Reached a deal with shortstop Rafael Furcal on a two-year deal worth about $14 million.
RAMIREZ UPDATE: Manny Ramirez applied for reinstatement to Major League Baseball, and his suspension for a second failed drug test was cut from 100 games to 50 because he sat out nearly all of last season.