Maclin was listed as doubtful Thursday with a knee injury after not practicing this week. Maclin, who is second among Baltimore wide receivers with 40 catches for 440 yards, was knocked out of Sunday's game after injuring his knee and didn't return.
The Ravens (8-6) can clinch a wild-card spot if they win their last two games against the Colts and Cincinnati Bengals.
Chris Moore would replace Maclin in the starting lineup against Indianapolis, which ranks 30th in the league in pass defense. Moore has shown flashes this season, catching 15 passes for 213 yards and two touchdowns.
In his first season with the Ravens, Maclin has been a disappointment. He is on pace to set career lows for catches and yards per catch (11.0).