Coach Adam Gase declined to say Sunday whether Brock Osweiler or David Fales would be first off the bench to replace Tannehill, but said he expects to keep all three all season. Even so, the Dolphins found room on their roster to add rookie quarterback Luke Falk, claimed one day after being waived by the Tennessee Titans.
Falk, a sixth-round draft pick, could make an immediate impact by providing insight into the Titans' playbook under a new coaching staff. The Dolphins open the season against Tennessee on Sept. 9.
The margin between Osweiler and Fales in the competition for the No. 2 job was thin throughout training camp, Gase said.
''It's day to day,'' he said. ''I feel like it goes back and forth. It's one of those things - whoever has the best protection on that particular night, it seems that guy has a good night in preseason. That's what is always going to make it tough deciding who's the backup. You're guessing a little bit.''
Gase said he may list the No. 2 quarterback as ''Osweiler or Fales'' on the depth chart preceding the Titans game.
''Nothing changes for me,'' Osweiler said. ''I'm just solely focused on trying to get better. Whoever is the 2, whoever is the 3, that's something I can't control.''
The Dolphins are underdogs in the opener despite being at home, and coming off a 6-10 season in 2017, they're widely projected to finish below .500 again. But in the wake of cuts to reach the 53-man roster limit, Gase sounded as optimistic as every other coach at the end of the preseason.
Roster turnover has resulted in a better locker-room culture, Gase said, and he anticipates the improvement to be reflected in the win-loss record.
''I like our team. We're a team,'' he said, emphasizing the last word. ''That's the best part about what we have going on right now - that locker room. I'm not really worried about what anybody else thinks about that. When you're not there every day and around these guys, you don't know. You can look at a piece of paper, but that's why they play the games.''
Miami should be better at quarterback, with Tannehill returning after missing last season following left knee surgery. But it's unclear whether holdover Fales or newcomer Osweiler represents an upgrade over the departed Matt Moore, who had been Tannehill's backup since 2012.
The play of both Osweiler and Fales was spotty during training camp. Gase works closely with quarterbacks and saw enough potential to want to keep them around.
''You talk about that being one of the most important positions,'' Gase said, ''and our thought process is we're going to try to develop guys and get them ready to go. And if we're ever in a situation where we need the next guy, we want to make sure we have the right guy. And we're going to keep working with the two guys we've got.''
In other roster moves, Miami claimed receiver Tanner McEvoy off waivers from New Orleans, released tackle Sam Young, and placed center Jake Brendel and linebacker Mike Hull on injured reserve.
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