The reason for Shalrie Joseph taking an indefinite leave of absence from the New England Revolution is that he he has entered MLS's substance abuse and behavioral health program, reports Frank Dell’Apa, who cites team sources.

New England had announced on Monday that the 31-year-old team captain, a key figure for the Revs since 2003, was attending a personal matter. Joseph suffered a hip flexor strain before the season and played in only one of the team's five games, but club vice president of player personnel Michael Burns and Joseph’s agent, Ron Waxman, had confirmed the leave of absence was not soccer-related, and did not involve contract problems or injury.

"I can’t confirm or deny anything," said Burns on Tuesday. MLS policy regarding drug testing restricts comments by team administrators.