Headley was able to hit in the batting cage for the first time since suffering the injury. A switch-hitter, Headley was only allowed to hit left-handed so he wouldn't put too much stress on the calf. But this was a step ahead in his rehabilitation.
"It's feeling great," he said. "As the doctor said, it's as good as we can ask for."
Headley suffered the injury in a rundown drill earlier in camp and an MRI showed that he had a Grade 1 strain of the gastrocnemius muscle, which is one of three muscles in the calf.
Headley said the pain started to subside almost immediately, and the crutches he used shortly after the injury to protect the calf were gone by the second day.
At this rate, Headley could possibly return to action by mid-month, which is still plenty of time for him to get his work in before Opening Day on March 30 against the Dodgers.
Headley, in the past, has estimated that he only needs 15-20 at-bats from each side of the plate before he's ready for the regular season.
The Padres have used several players at third base in Headley's absence, including Ryan Jackson, who got the start there Monday against the Giants. Jackson is trying to make the Opening Day roster as a reserve infielder. He's impressed the coaching staff at shortstop, too.
Corey Brock is a reporter for MLB.com. Keep track of @FollowThePadres on Twitter. This story was not subject to the approval of Major League Baseball or its clubs.