(Agencies)
Updated: 2007-12-07 11:01

NEW YORK - Outfielders Jose Guillen of the Kansas City Royals and Jay Gibbons of the Baltimore Orioles have been suspended for 15 days for violating Major League Baseball's joint drug prevention and treatment program.

The bans will begin at the start of the 2008 season, league commissioner Bud Selig said in a statement on Thursday.

Guillen, 31, reached agreement with the Royals on a three-year contract earlier on Thursday.

A native of the Dominican Republic, Guillen is a veteran of 11 seasons in the major leagues and batted .290 with 28 doubles, 23 home runs and 99 RBI for the Seattle Mariners last season.

Gibbons, 30, hit .230 last season for the Orioles with six home runs and 28 RBIs in 84 games.

The baseball commissioner's office said it had found "insufficient evidence" of doping violations after completing investigations of Scott Schoeneweis, Gary Matthews junior, Troy Glaus and Rick Ankiel.