"If I do the stem-cell and it fails, it could lead to another Tommy John and I might not ever pitch again," Billingsley said. "This is my best chance to pitch again. With stem-cell, the percentages were not in my favor and it was playing with fire."
The flexor tendon runs alongside the ulnar collateral ligament that tore and was transplanted last year in a Tommy John procedure. If the flexor tendon tears further after an injection and rehab, it could compromise the repaired ligament.
Billingsley, 29, is receiving $12 million in the final guaranteed year of a three-year, $35 million contract that includes a $3 million buyout or $14 million salary for 2015.
"I'm not really worried about that," Billingsley said of free agency. "I'm worried about being healthy."
A former All-Star, he hasn't pitched for the Dodgers since April 15, 2013. He twice had rehab assignments this year shut down because of discomfort that turned out to be the flexor tendon, diagnosed the first time as tendinitis.
"I'm flustered," said Billingsley. "This is not the way I wanted to spend two years of my life in rehab."
The flexor tendon surgery is less invasive than Tommy John reconstruction. Billingsley said he will rehab for three months, start throwing in December and be ready for next Spring Training.
ElAttrache told Billingsley that even if he hadn't needed Tommy John surgery last year, his flexor tendon was likely to have torn "sooner or later."
Ken Gurnick is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.