ST. LOUIS -- Jake Peavy is out for the season after fracturing his eighth right rib in Tuesday's Division Series opener against St. Louis.
Initial X-rays were negative, but the Padres sent Peavy to Barnes Jewish Hospital in St. Louis for an MRI, which revealed the fractured rib. A team spokesman said Peavy might have also broken his ninth rib, and that additional tests were being done.
Padres manager Bruce Bochy said the team didn't know when Peavy suffered the injury.
St. Louis won Game 1 at home 8-5.
The Padres had planned to have Peavy throw Game 4 of the series Sunday at Petco Park. Adam Eaton is likely to fill that spot if San Diego forces a fourth game.