The club believes Lohse's injury is relatively mild and hopes that he won't be sidelined for more than 10-15 days -- though of course he can't return to the active roster for at least 15. Lohse suffered the injury when he was running to first base on a single during Friday night's 4-0 Cardinals loss to the Padres.
The Cards have yet to announce who will take Lohse's spot in the starting rotation, though they don't have to decide right away. Following Monday's off-day, Chris Carpenter can pitch on regular rest Thursday and John Smoltz can pitch on Friday, so the fifth spot wouldn't come up until Aug. 29 at home against the Nationals.
"We [announced Adam] Wainwright and [Joel] Pineiro, and then we'll hold on Thursday," manager Tony La Russa said. "We'll just see how it goes -- see if we want to bring Carp back on time or give him an extra day. ... What Lohse being out means is that we're back to examining all the alternatives."
Boggs is certainly one candidate to start, as is Brad Thompson. The club would lean against pitching rookie Blake Hawksworth.
"If you had to drag it out of me, my opinion is that we more need the reliever than we do the starter in that spot," La Russa said.
Boggs was sent down on Thursday when the Cardinals signed Smoltz. Typically, a player must stay in the Minors for 10 days after he is sent down, but that rule is waived when the player is recalled to take the place of an injured player.
Matthew Leach is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.