Per Kevin Bowen of 1070 The Fan, Colts head coach Chuck Pagano announced Davis would miss Week 1.
Davis injured his groin on Aug. 29, and Pagano told reporters it was "significant."
The Colts are starting the 2017 season banged up, with Davis joining quarterback Andrew Luck as two of the team's key players on the sidelines for the opener.
Davis has been one of the Colts' best defensive players since being acquired in a trade with the Miami Dolphins prior to the 2012 season. He was named to the Pro Bowl in back-to-back seasons in 2014-15 after recording a total of eight interceptions in 31 games.
Last season saw Davis' overall performance decline. The 29-year-old finished 98th in Pro Football Focus' cornerback grades with a 47.3 mark, a drop of nearly 50 points from his high-water mark in 2014 (94.6).
With Davis sidelined again, the Colts could turn to rookie Quincy Wilson or second-year cornerback Christopher Milton.