Tannehill was limited in practice Friday and has been listed as questionable for Sunday's showdown opposite fellow first-round draft pick Andrew Luck. Tannehill practiced all three days for the Dolphins, though backup Matt Moore saw increased snaps.
The Miami Herald reported Friday that the Dolphins are cautiously optimistic Tannehill will play Sunday. The team will re-evaluate the QB on Sunday. He will continue to receive treatment in Indianapolis.
If Tannehill starts, he could be on a short leash if he struggles with mobility. The Dolphins have one of the league's top backups in Moore, who helped lead Miami to an easy win over the New York Jets last Sunday after Tannehill left in the first quarter with thigh and knee injuries.
Yahoo! reported that Tannehill had the knee drained off fluid at least twice this week.
In other injury news, Dolphins wide receiver Brian Hartline has also been listed as questionable after landing on the injury report on Thursday with a groin issue. Hartline is the Dolphins' leading receiver this season.
Follow Dan Hanzus on Twitter @danhanzus.