The Cardinals, desperate for rotation help, have signed right-hander Tomo Ohka to a minor-league contract, FOXSports.com has learned.
Ohka, 31, will start Wednesday night for the Cardinals' Class AAA Memphis affiliate in Round Rock, Tex., against the Astros' top farm club.
If he is not promoted to the majors within 10 days, he will have the right to pursue other opportunities, according to a source with knowledge of his deal.
Ohka was designated for assignment by the Blue Jays on June 7 after going 2-5 with a 5.79 ERA in 10 starts. The Jays were unable to trade him, and he was released Tuesday.
The Cardinals, whose 5.63 rotation ERA is the worst in the National League, placed right-hander Braden Looper on the disabled list Monday with a shoulder sprain.
Right-hander Chris Carpenter and left-hander Mark Mulder also are on the DL. The Phillies also pursued Ohka, but wanted him to make four starts at Class AAA rather than the two he will make at most with the Cardinals.