NEW YORK — OF Marlon Byrd was suspended 50 games by Major League Baseball on Monday after testing positive for a performance-enhancing substance. Major League Baseball said Byrd, 34, tested positive for Tamoxifen, which can reduce side effects of steroid use and increase testosterone. It is often used to treat breast cancer patients."I made an inexcusable mistake," Byrd said in a statement released by the players' association. "Several years ago, I had surgery for a condition that was private and unrelated to baseball. Last winter, I suffered a recurrence of that condition and I was provided with a medication that resulted in my positive test. Although that medication is on the banned list, I absolutely did not use it for performance enhancement reasons." Byrd is a free agent and will be placed on the restricted list for the duration of his suspension, which began immediately. In 2009, Byrd admitted using supplements provided by Victor Conte , the founder of the Bay Area Laboratory Co-Operative. BALCO was at the center of a wide-ranging investigation involving performance-enhancing drugs that enveloped several top-level athletes, including Marion Jones , Tim Montgomery and Barry Bonds . Conte pleaded guilty to steroid distribution in July 2005 and served four months in jail. Byrd said the supplements were all okay to use under MLB rules. He had never been suspended for failing a PED test. AL DOMINATES: The American League went 142-110 against the National League in interleague play, a .563 winning percentage. The AL has won the series for nine straight years and is 2,079-1,883 (.525) in that stretch. TEJADA RELEASED: The Orioles released INF Miguel Tejada from Triple-A Norfolk at his request. Tejada, 38, a former AL MVP, batted .259 with no homers in 36 games while playing third base for Norfolk. BLUE JAYS: 1B Adam Lind , who was demoted to Triple-A Las Vegas on May 16 because of concerns about his conditioning, was promoted after batting .392 with eight homers in 32 games. CUBS: 1B Anthony Rizzo , one of the team's top prospects, was promoted from Triple-A Iowa. Rizzo, 22, batted .345 with a Pacific Coast League-high 23 homers in 69 games for Iowa. INDIANS: RHP Jeanmar Gomez , whose ERA went from 3.19 to 5.18 over his past six starts, was demoted to Triple-A Columbus. RHP Zach McAllister is expected to be recalled from Columbus on Thursday. METS: Manager Terry Collins said RHP Bobby Parnell will serve as closer while RHP Frank Francisco is on the 15-day disabled list with a left oblique strain. … The contract of LH reliever Justin Hampson was selected from Triple-A Buffalo, and OF Vinny Rottino was designated for assignment. NATIONALS: INF Mark DeRosa was activated from the 15-day disabled list after missing two months with a strained oblique. OF Xavier Nady went on the DL with right wrist tendinitis. PHILLIES: Backup C Brian Schneider , who sprained his right ankle in a collision with Rays INF Sean Rodriguez on Sunday, went on the 15-day disabled list. C Erik Kratz was promoted from Triple-A Lehigh Valley. REDS: CF Drew Stubbs was activated from the disabled list, restoring the everyday lineup to full strength. Stubbs went on the DL June 15 after pulling muscles in his left side during a swing. ROCKIES: Rookie RHP Alex White was optioned to Triple-A Colorado Springs one day after his third straight poor start. White was 2-6 with a 6.45 ERA in 10 starts. TWINS: Closer Matt Capps went on the 15-day disabled list with inflammation in his right (pitching) shoulder. LHP Glen Perkins and RHP Jared Burton will likely fill in for Capps.