"Nothing at all," Peterson said Saturday.
With Headley on the disabled list for another strain of that same calf, the Padres have taken a long look at Peterson at third base. He made his sixth start there Saturday against the D-backs.
Peterson, who was promoted from Double-A San Antonio on April 25, entered the game hitting .211 in his first 19 big league at-bats.
Defensively, he's made one error in his first seven games there -- including five starts before Saturday. As you might imagine, the hot corner has taken some getting used to.
His indoctrination in Spring Training to the position proved to be a blessing, he said.
"I think it helped me tremendously to take some ground balls right away there and get some reps in practice and in games," Peterson said.
Peterson, the 58th overall selection in the 2011 Draft out of McNeese State, was a shortstop during his first three Minor League seasons. Even when he reported to San Antonio, he mostly played shortstop but played third base once.
"Probably the biggest thing is when the ball comes off the bat at a different angle. It's still the left side of the diamond, but you've got to be able to pick up the contact point out front since the ball is coming quick," Peterson said. "It's just minor things. I think the more reps I get and the more I play, the better that I will be at it."
So far, Black likes what he's seen in Peterson.
"The makeup itself … this guy is a competitor and he doesn't scare off," Black said. "He's a clear thinker. He was a college football player, too, so there's some toughness to him. I like how he goes about it. I like a lot of the intangibles."
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.