Rea will start Game 1 of Wednesday's doubleheader against the Cardinals after Tuesday's game was postponed, the San Diego Union-Tribune's Dennis Lin reports.
He will receive an extra day of rest following Tuesday's postponement, and will face Cardinals starter Carlos Martinez in his 17th start of the season. Paul Clemens will start Game 2 of the doubleheader for the Padres, with Andrew Cashner taking the ball Thursday.