Josh Johnson will try to resume his throwing program Tuesday in South Florida, a significant step toward his effort to return to the Marlins' starting rotation before the end of the season. "We'll try to start building him back up,' General Manager Mike Hill said Monday. Johnson could play catch in long-toss sessions for at least a week before he moves to a mound, where he would then try to throw at least three bullpen sessions every other day. If that goes well, he'd pitch at least one simulated game and then make two or three rehab starts. Barring another setback, Johnson could return to the Marlins by September. But he started a throwing program in June before being shut down because of discomfort. Johnson's last start was May 16, a day before he went on the disabled list with right shoulder inflammation. Last year, he missed the final three weeks of the season with a strained back muscle and sore right shoulder. A two-time All-Star, Johnson is 3-1 with a 1.64 ERA in nine starts this year. His rotation spot is now being plugged by rookie left-hander Brad Hand, who make his seventh start Tuesday. "His injury kind of helped my situation, but we don't want to have our No. 1 guy down,' said Hand, who is 1-3 with a 2.73 ERA in six starts.