"Worst-case scenario, if I miss a game or two in the regular season, that's better than missing 30," Headley said Sunday as he massaged his right calf with a roller.
Headley hopes he can play in an exhibition game within a week.
"The at-bats I'm not worried about because I'll go down to the minor leagues and I can get five, 10, 15 in a day if I want," Headley said. "It's more being on my feet, bouncing back, getting my legs conditioned to play every day. If I can get a week to 10 days of games, then I'll feel really good."
Headley led the National League with 115 RBIs in 2012 before his numbers dipped last season. He signed a one-year, $10.5 million contact in January and has said he doubts the two sides can reach an agreement on a long-term deal before the start of the regular season.
The Associated Press contributed to this report.