The Padres were a pitch away from a 1-0 win but the Cards scratched out a run off Heath Bell with two outs in the ninth so it was on to extra innings.
Kevin Correia pitched his heart out. He held the Cardinals scoreless even though he allowed five hits and walked six over six innings.
For Hairston, the winning run was his second homer of the season and second game-winning home run in two nights. On Tuesday night, Hairston's homer was the only run in a 1-0 win.