Colorado Rockies outfielder Jorge Piedra has been suspended for 10 days for violating Major League Baseball's new doping policy.

The office of baseball commissioner Bud Selig said Monday that the suspension begins with Colorado's game against the Arizona Diamondbacks in Phoenix Monday night.

Piedra spent just one day with the team last week before being sent back down to AAA Colorado Springs of the Pacific Coast League on Thursday. He is the second player to be publicly identified under the baseball's new doping rules. Tampa Bay outfielder Alex Sanchez was suspended for 10 days last Monday.

Under the policy that took effect last month, steroids and other performance-enhancing substances are the only drugs to draw a 10-day suspension. Baseball officials and the players' union agreed they would not disclose the exact substance involved in the positive test.

Some information for this report provided by AP and AFP.