“The Diamondbacks needed an additional pitcher in the rotation. The need would have been for two additional pitchers in the rotation, except Brandon Pfaadt stepped up his game just in time for the playoffs. Reasons for that shortfall:
Madison Bumgarner lost his effectiveness (In April, his last four games averaged just over 4 innings with an ERA of 10.26.
Zack Davies lost his effectiveness (In September, his last 5 games averaged 4 innings with an ERA of 7.20.
Mike Hazen failed to add to the rotation despite many attempts.