NEW YORK — Outfielder Marlon Byrd was suspended for 50 games by Major League Baseball Monday after testing positive for a performance-enhancing substance. MLB said the 34-year-old Byrd 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. “Last winter, I suffered a recurrence of an injury and I was provided with a medication that resulted in my positive test." — AP