The Rockies placed Karros on the 7-day injured list Sunday due to a concussion.
The 24-year-old was activated from the concussion IL on Friday but will quickly return after experiencing additional symptoms. Karros will be sidelined for at least another week while he goes through the league's protocols. Ryan Ritter was called up from Triple-A Albuquerque in a corresponding move and is starting at second base Sunday against the Guardians, with Willi Castro sliding to the hot corner.