Hairston rejoined the club Monday after being sidelined since April 6 with a strained side muscle.
Souza had one hit in eight at-bats since coming up from the minors on April 27.
Manager Matt Williams said catcher Wilson Ramos could join the team later this week. Ramos has been out with a broken bone in his left hand. He was scheduled to catch nine innings for Double-A Harrisburg on Monday.