The development is a significant relief to the 39-year-old right-hander, who has been on the disabled list for more than a month.
"The doctor, at one point, was talking about surgery," Peralta said Friday.
Peralta said the source of his shoulder problems is a nerve that runs from the neck to triceps on his right arm. The nerve was pinched, and Dr. Robert Watkins Jr. talked to him about treating the problem by removing a disk from his back.
But Peralta's condition gradually improved. About a week ago, he started playing catch.
"That," Peralta said, "was a big relief."