Armando Salguero of the Miami Herald reported that the league is looking into why Tannehill was mysteriously unavailable for Sunday's game against the Chicago Bears. Tannehill was listed as questionable with a right shoulder injury on Friday despite being a full participant in practice throughout the week.
Coach Adam Gase initially was defensive when asked about the development surrounding Tannehill after the overtime win over the Bears. He later said he expects Tannehill to play again this season and that he'll be the starter when he does return, but isn't exactly certain when that will be.
"I'm not sure. I really don't know. I don't know the answer. It's day-to-day. It's really going to come down to how he feels," Gase said on Monday.
. Tannehill was spotted at practice Wednesday, but was not throwing the ball during the portion open to the media.
For the season, Tannehill has completed 85 of 129 passes for 972 yards with eight touchdowns and five interceptions.
Backup Brock Osweiler started in place of Tannehill on Sunday and completed 28 of 44 passes for a career-high 380 yards, three touchdowns and two interceptions.
Osweiler will take first-team reps until Tannehill is ruled ready to play.
The Dolphins (4-2) host the Detroit Lions (2-3) on Sunday.