This time, Carpenter has a contusion after fouling a ball off the top of his right foot in the seventh inning of Monday's 7-0 win against the Pittsburgh Pirates.
The move comes just days after Carpenter had rejoined St. Louis after the All-Star break. He had been sidelined since June 29 with a lower back strain.
X-rays on the foot came back negative.
"I couldn't walk this morning," Carpenter said Tuesday, according to the St. Louis Post-Dispatch. "Pretty uncomfortable. ... It's just some bone contusion and some swelling in the joint. The fact that it's in the joint ... I'm not able to walk real well.
"Hopefully, the swelling and inflammation goes down and then I can start doing what I need to do."
Carpenter is batting .215 with 10 home runs and 29 RBIs this season.
In the corresponding roster move, the Cards recalled rookie infielder Edmundo Sosa from Triple-A Memphis.