Lenny Dykstra, the troubled ex-Phillies star, is expected to be released from a California prison Sunday, 15 months into his three-year term, according to sources.

Dykstra, 50, pleaded no contest in October 2011 to three grand theft auto charges and one count of filing a false financial report, the latest in a series of downfalls in a tragic slide.

After attending a drug and alcohol rehabilitation program, he was sentenced to three years in prison on March 5, 2012.

"I was surprised they let him out before the three years, to be quite frank with you," said Christopher Frankie, author of Nailed: The Improbable Rise and Spectacular Fall of Lenny Dykstra. "Because he blatantly disobeyed the court, and a lot of the stuff was very brazen. He was doing it in the full view of law enforcement."

Dykstra retired at age 33 in 1996 after a 12-year career with the Mets and Phillies. He led the Phillies to the National League pennant in 1993, when he batted .305.

"I hope, for his sake, his family's sake, and the public's sake, that he doesn't return to his criminal past," Frankie said.

"I think people in this country really love a comeback story, so he certainly has that opportunity," he added. "But I'm not convinced that's the path he's going to take."