This isn't how they drew it up.

But the Dolphins will surely take it.

Miami survived a Tua Tagovailoa injury, a late special-teams blunder and a last-minute rally by the Buffalo Bills to secure a 21-19 win on Sunday to improve to 3-0 and take control of the AFC East.

Tagovailoa left in the first half after a head injury left him wobbling on the field. But he returned to start the second half, where he led the Dolphins to the half's only touchdown that ended up being the difference in the game.

'Butt punt' gives Bills late hope

The Bills threatened late, but came up short on a Dolphins goal-line stand while trailing 21-17. But their defense gave them another shot, forcing Miami to punt from inside its own end zone with 1:33 remaining. Thomas Morstead's punt bounced off the back of teammate Trent Sherfield and out of the back of the end zone for a safety.

But Buffalo's final drive came up painfully short. Isaiah Mckenzie wasn't able to get out of bounds at the Miami 41-yard line after a 12-yard gain on a pass from Josh Allen, and the clock expired to secure the Miami win.

The result of the play left Bills offensive coordinator Ken Dorsey furious.

The game was billed as a matchup of explosive offenses after the Dolphins and Bills each scored 40-plus points in Week 2 wins. But attrition took its toll on the Bills as sweltering Miami heat and injuries in the secondary forced them to rotate reserves into starting positions on both sides of the ball.

Should Tua have been allowed to play?

Miami, meanwhile, appeared to face a second half without Tagovailoa after a head injury left him wobbling in the second quarter. With the game tied at 14-14, Bills linebacker Matt Milano shoved Tagovailoa backward after the Dolphins quarterback released a pass. The back of Tagovailoa's head bounced off the turf.

He got up on his own. But he immediately fell back to the ground as he struggled to find his footing. He left the field with the assistance of trainers before the Dolphins listed him as questionable with a head injury.

Despite the injury, Tagovailoa returned to start the third quarter and played the remainder of the game. The NFLPA has reportedly started an investigation to find out how Tagovailoa cleared concussion protocol and was allowed to return to the field.

Miami's home-field heat advantage

The Bills struck first after the break with a field goal to take a 17-14 lead that concluded a 20-play, 87-yard drive on their first third-quarter possession. With the temperature in the 90s and the heat index on the field more than 100 degrees, Buffalo struggled to keep its players on the field. While Miami players sat on their sideline in the shade, the design of Hard Rock Stadium left Buffalo players sweltering in the afternoon sun.

Right tackle Spencer Brown left the game and didn't return with what the Bills assessed as "heat illness." Right guard Ryan Bates and center Greg Van Wroten — who was already subbing for injured starter Mitch Morse — also appeared to be impacted by the conditions and missed game time. Buffalo started the day with several players ruled out with injury, including safety Micah Hyde, who's been ruled out for the season with a neck injury.

Tua-Waddle connection sets up go-ahead score

The Dolphins responded to the field goal two possessions later with a 72-yard scoring drive highlighted by Tagovailoa's 45-yard pass to Jaylen Waddle. The play set up a 3-yard Chase Edmonds touchdown run to give Miami a 21-17 lead with 10:05 remaining.

The Bills then responded with their second marathon drive of the half. After a touchback, the drove the ball inside the Miami 20-yard line while taking more than six minutes off the clock. From there, they ran six more plays and forced Miami to call timeout to preserve game clock in anticipation of a go-ahead Bills score. But Buffalo didn't find the end zone. Allen's fourth-and-2 pass bounced off the turf short of intended target McKenzie, and Buffalo turned the ball over on downs. The play concluded a 17-play, 73-yard drive that took 8:19 off the clock

Then chaos ensued. The Dolphins were able to run only 13 seconds off the clock before Morestead's punt resulted in a safety. Fortunately for Miami, Buffalo ran out of time before finding field-goal range on its ensuing possession.

Buffalo dominated the ball on Sunday with a 40:40-19:20 edge in time of possession. But it didn't capitalize. Two second-half Bills possessions consisted of 37 plays for 160 yards while taking 17:41 off the clock. They resulted in a total of three Buffalo points.

Meanwhile, the Dolphins got just enough out of their offense after Tagovailoa's return. Tagovailoa finished completing 13-of-18 pass attempts for 186 yards and a touchdown. Waddle accounted for the bulk of the passing production with 102 yards on four catches.

Allen, meanwhile, had another big day, completing 42-of-63 attempts for 400 yards with a pair of touchdowns while adding 47 yards on the ground. He faced pressure from the Dolphins pass rush all day, taking four sacks and losing a fumble. It was enough to disrupt Buffalo's normally high-scoring offensive attack.

Now the Dolphins are the unexpected Week 3 AFC East leaders as the Bills fall to 2-1. Miami will also have some questions to answer this week about Tagovailoa.