The Giants had announced the three starters for the Astros before the break, and manager Bruce Bochy confirmed during Thursday's team workout that the lefty Zito will pitch ahead of Vogelsong so that there wouldn't another another left-hander right in front of the lefty Bumgarner.
"It's just breaking up the lefties," Bochy said. "We talked to them all, they're all good, and that's the plan coming out of the break here."
Bochy also didn't dismiss reports that he and general manager Brian Sabean will consider skipping Lincecum's spot in the rotation if he struggles again on Saturday.
"I don't want to put added pressure on him, but sometimes you have to do what's right," Bochy said. "I said this at Pittsburgh, but I think Timmy's going to bounce back and have a better second half. We certainly need him."
Lincecum's 6.42 ERA was the highest among qualified pitchers in the first half, and lasted 3 1/3 innings in both of his July starts before the break, giving up a combined 13 earned runs for a 17.55 ERA.