OAKLAND -- Giants manager Bruce Bochy confirmed Tuesday that closer Brian Wilson will start the season on the disabled list with a strained oblique muscle on his left side.An official announcement is expected on Wednesday. Wilson underwent a successful bullpen session on Tuesday in Scottsdale, Ariz., marking the first time he has thrown off a mound in nearly two weeks. He appeared in just five Cactus League games this spring because of the strain, along with an early bout of back tightness. "He felt great today," Bochy said. "I'm very encouraged with his progress, and we'll decide tomorrow his next move. I don't think he'll start the season with us, but it's good to see him feeling good, and he's letting it go." Even though the All-Star hurler will be on the disabled list when the team opens the season on Thursday in Los Angeles, the right-hander could return as early as April 5 because the team can backdate his DL assignment up to 10 days. In the meantime, Bochy said he could potentially rely on a closer-by-committee approach in Wilson's absence. He mentioned Jeremy Affeldt, Sergio Romo and Javier Lopez as options in that role. "I'd like to get on somewhat of a consistent basis with a closer, but I'm gonna get with those guys and tell them what my thinking is," he said.