Brown's status is now week-to-week, a source told ESPN's Adam Schefter on Monday.
The injury occurred in the first quarter. Brown played only eight snaps against the Colts. He was targeted twice but didn't have any receptions. Brown has seven receptions for 92 yards and a touchdown after three games.
Second-year receiver Nick Westbrook-Ikhine took Brown's spot in the lineup and finished with four receptions for 53 yards and a touchdown as the Titans outlasted the Colts, 25-16.
Tennessee will take on the New York Jets on Sunday.