Coweta County coroner Richard Hawk, who told The Associated Press that an autopsy began Tuesday, said Hanson, 29, was found by sheriffs Sunday "unconscious and unresponsive".
Hanson, a 6-foot-6 right-hander, pitched for the Braves from 2009-12, winning at least 10 games each season. He spent the 2014 season with the Chicago White Sox Triple-A club, and spent 2015 in the San Francisco Giants organization. He rose through the team's farm system, and finished third in the Rookie of the Year voting after posting a 2.89 ERA over 21 starts in 2009. Another former Braves teammate, Jordan Schafer, posted on his Twitter account at 11:06 p.m.: "This breaks my heart".
He broke into the major leagues as a highly-regarded pitching prospect after being selected in the 2005 MLB Draft.
"We are incredibly saddened to learn of Tommy's tragic passing". He was a favorite in the clubhouse and with our staff and he will be truly missed by everyone in Braves Country. "He was not "like" a brother to me, he was my brother and I'm going to miss him so much". We all loved and pulled for him.
However, Bond responded via text and said he was staying silent for now out of respect for Hanson's family. The league held a moment of silence for Hanson on Tuesday.
Sheriff's officials described the emergency call for former Atlanta Braves and Los Angeles Angels pitcher Tommy Hanson before his death as an "overdose", but they don't provide other details in a report released Wednesday.