Colts cornerback Vontae Davis, who has missed the last four games with an injured left knee, is expected to start Sunday at Detroit.
Interim coach Bruce Arians says safety Tom Zbikowski will not make the trip because of a right knee injury. Sergio Brown will likely replace Zbikowski in the starting lineup, and Brown will split time with backup Joe Lefeged.
Arians also says coach Chuck Pagano is starting his third and final round of chemotherapy Friday. Pagano has been on leave from the Colts (7-4) since being diagnosed with leukemia Sept. 26
Arians says his close friend is doing "very well" and that after this next round of treatment, doctors will monitor Pagano's white blood-cell count.
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