Betancourt, 38, said after a Tuesday night loss he did not plan to pursue surgery and instead planned to rehab the arm through platelet-rich-plasma treatment. But he told the Deportes Union Radio network Thursday he changed his mind after consulting with doctors.
"I took the decision last night, alongside doctors," Betancourt said on the radio show Los Cronistas. "They told me there was little chance of recovery with current treatment."
Because he did not initially plan to have the surgery, many expected that Betancourt had pitched his last Major League game. He was in his fifth year with the Rockies, his 11th in the big leagues, when he tore the ligament in an Aug. 22 loss to the Phillies.
But the surgery is a strong indication he plans to return to a big league mound.
"It would be sad to come to the end of my career this way, after all I've been through," he said. "This motivates me to go on."
Betancourt will see noted Dr. James Andrews on Wednesday and plans to have the surgery in September, he said in the interview.
"I know if my arm feels healthy, I can still pitch for a few more years," he told the network from his Orlando, Fla., home.
Rex Brothers, 25, has done an admirable job in Betancourt's absence and appears a lock to be the Rockies' closer of the future. That makes it unlikely the Rockies would pick up Betancourt's mutual option for 2014.
"From now on, my career will move forward with the team that gives me an opportunity," Betancourt told the Venezuelan station. "Colorado has not closed the doors on me though."
Betancourt converted 16 of 17 save opportunities before he blew saves on consecutive nights against the Phillies, the second ending with the pitcher fearing the worst, an MRI on Tuesday confirming he had a fully torn UCL.