BUFFALO, N.Y. - A Toronto sports doctor has pleaded guilty in Buffalo, New York to smuggling human growth hormone and other unapproved drugs into the U.S. to treat pro athletes.

The indictment against Doctor Anthony Galea did not name any clients.

However, prosecutors say the list includes at least 20 athletes, including pro golfers as well as pro baseball and football players.

They allege the client were treated in their homes, hotels, and friends' houses over a two-year period that ended in September, 2009.

Brian Greenspan, Galea's lawyer, says his client did it for the sole purpose of helping heal patients' injuries.

Galea, who is 51, was released until he's sentenced on October 19th.

He could get up to two years in jail and a 40-thousand-dollar fine.