The Cardinals placed Palmer (arm) on injured reserve Thursday, Kyle Odegard of the team's official site reports.

EDGE Analysis

In the aftermath of Sunday's loss to the Rams in London, head coach Bruce Arians relayed Palmer would likely need eight weeks to recover from a broken left arm. A second opinion was ordered up, though, revealing Palmer may be able to return within 4-to-6 weeks. The veteran signal caller has since undergone surgery, and the former was in fact the correct approximation, resulting in Palmer's placement on IR. While he focuses on rehab and a potential return as early as Week 16, the Cardinals will turn over the offense to Drew Stanton.