Tannehill hasn't played in a game since injuring his right shoulder Oct. 7 at Cincinnati, and he was ruled out on Wednesday by coach Adam Gase.
Tannehill's progress has been slow, and he hasn't thrown a pass in the open period of practice since Oct. 11. He will likely need multiple full practice days in a row without any setbacks before he's able to play in a game.
The shoulder is still bothering Tannehill, which isn't a good sign considering that he often plays through minor ailments. Gase clarified that Tannehill's injury isn't a sprain, but he has yet to make public the actual injury. He has said surgery still isn't an option for Tannehill at this point.
"This is a rest type thing," Gase said.
There's a reasonable chance that Tannehill won't see the game field again until after the Dolphins' Week 11 bye. Their next game after the bye would be Nov. 25 at Indianapolis.
Gase said earlier this week that Tannehill's injury is "unusual," with "a lot of gray." He says Tannehill has been throwing with trainers, but he doesn't yet have the velocity or power required to throw in real action.
Osweiler has gone 1-2 in three starts in place of Tannehill, but he hasn't been the main reason for the losses. In fact, Gase said Osweiler has done "a great job" of replacing the starter, but Tannehill will return to the role when he is ready.
"I'm playing as hard as I possibly can so hopefully I never have to go back to the bench," Osweiler said.
"Your mentality in this league is when you get your opportunity to play, you never give that guy his job back," he added. "That has to be your mentality, and if that's not your mentality then you're just in the wrong business. That's nothing personal against anybody."
Tannehill completed 66 percent of passes for 972 yards, 8 touchdowns and 5 interceptions in his five games. Osweiler has completed 64 percent of his passes for 895 yards, 6 TDs and 3 INTs in his four games (three starts).