Sidelined for two weeks with a strained right triceps, Lackey will be put on a program that could have the American League's 2007 ERA champion and 19-game winner back at the top of the rotation in early May, manager Mike Scioscia said.
"John's been coming along great in his rehab," Scioscia said. "I think we have a shot at having him back in early May, and that would be a real shot in the arm, obviously.
"We've got to work him up to it, starting with three bullpen sessions, then three batting practices. Then we'll get him in a game and build his arm strength. We might be able to accelerate some of it because he's already done some throwing in Arizona."
Scioscia said he spoke with Kelvim Escobar, who'd addressed a fear on Wednesday that his career could be over with a tear in his pitching shoulder.
"Kelvim was emotional when he said that," Scioscia said. "He told me he still has hopes of pitching this season -- and so do we."
Lackey and Escobar combined for 37 wins in 2007, forming one of the game's dominant starting tandems.
After forearm stiffness set him back early in camp, Lackey made one Cactus League start, going 1 2/3 innings on March 10 against the A's. Throwing during his side session two days later, he experienced discomfort in another area of the arm -- behind the elbow -- than the earlier ailment.
Examined by Dr. Lewis Yocum, the team orthopedist, Lackey was told that a triceps strain is similar to a hamstring pull.
"You've got to let it heal on its own and be patient," Lackey said at the time. "If I go out too early, I can end up setting myself back.
"It's no fun. It's definitely not where I wanted to be. I'll have to work hard, get the rest of my body stronger. It might be a little blessing if I'm a little stronger at the end of the season."
Opening the season on the disabled list will be a first for Lackey, who hasn't missed a start because of injury since breaking into the rotation in 2002 on his way to starting and winning Game 7 of the World Series against the Giants.
Lyle Spencer is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.