MIAMI GARDENS, Fla. -- New England is efficient enough without help, but Miami mistakes led to first-half 17 points as the Patriots defeated the Dolphins 23-16 Sunday to clinch their ninth AFC East title in 10 years.
The Patriots won their sixth straight game as they improved to 9-3 and guaranteed a 12th straight winning season.
New England converted a fumbled snap on a punt, a roughing-the-kicker penalty, and its 19th fumble recovery and 25th turnover, best in the NFL, into 17 points to gain control.
"When our offense is struggling, it is time for us to showcase how special we are," Patriots nose tackle Vince Wilfork said.
The Patriots' offense, which rolled up 108 points in the last two games and scored 219 points in the previous five wins, wasn't as productive against the Dolphins.
Quarterback Tom Brady, who has been on a roll, threw for 238 yards on 24-of-40 passing with a touchdown and an interception.
He understood the difference that good early field position made.
"The last three times that we've played down here in December we've lost," Brady said. "Those were important points. We would have liked touchdowns, but we need to execute better for that to happen."
With the AFC East title clinched, the Patriots already are facing questions about the playoffs and a possible return to the Super Bowl.
"December is when the good teams separate themselves," Brady said. "We have a lot of games to play before we start thinking about the playoffs."
The Patriots have back-to-back games with Houston, a contender for home-field position in the AFC, and then San Francisco, a possible Super Bowl opponent.
"We know that we have accomplished something," Wilfork said, "but in the grand scheme of things, we still have a long season to play. Upcoming wins are going to be very tough starting with Houston."
Dolphind punter Brandon Fields mishandled the snap on the first possession, giving the Patriots the ball at Miami's 12-yard line. It resulted in a 2-yard touchdown run by Steven Ridley and a 7-0 lead.
After Reshad Jones intercepted a Brady pass, the Dolphins converted it to a 44-yard field goal by Dan Carpenter, closing the deficit to 7-3.
The Dolphins stopped the Patriots after the ensuing kickoff, but Jimmy Wilson roughed punter Zoltan Mesko to give the Patriots new life.
Brady didn't waste it, completing five passes for 50 yards, including a 7-yard touchdown throw to Wes Welker for a 14-3 lead with 9:21 left in the half.
On Miami's next possession, quarterback Ryan Tannehill fumbled when hit by Trevor Scott, and Wilfolk recovered at the Dolphins 25. Stephen Gostkowski's 43-yard field goal increased New England's lead to 17-3 with 6:53 to play.
Tannehill, who completed 13 of 29 for 186 yards, was forced to play from behind the entire game.
"We left a lot of plays out there," Tannehill said. "Coach always says that you have to make the plays that are there."
The Dolphins finally mounted a drive in the final minutes of the half, going 80 yards in 12 plays with Tannehill scoring on a 2-yard run to trail 17-10 at halftime.
The drive was good mixture of running and passing, with seven rushes for 49 yards, including 13 yards by Tannehill and 30 yards by Reggie Bush. Tannehill complted four passes for 40 yards, including a 17-yard throw to Brian Hartline on third-and-3 at the New England 30.
The Patriots were not able to increase their lead until Gostkowski's 32-yard field goal made it 20-10 with 13:16 left in the game.
The Dolphins answered with a 34-yard field goal by Carpenter, closing to 20-13 with 8:28 to go.
The Patriots responded with a 16-play, 77-yard drive that took 7:18 off the clock and sealed the outcome. Gostkowski's 20-yard field goal concluded the scoring with 1:10 left.
Ridley gained 44 yards of the Patriots' 71 yards in nine carries on the drive as Brady threw only three passes.
"We wanted to score points, preferably a touchdown," Ridley said. "But the bigger goal right there was to close out the game. The time we took off the clock was the bigger accomplishment. Good teams finish games."
The Dolphins used an unusual strategy, choosing to have Carpenter kick a 42-yard field goal with 31 seconds left pulling to 23-16. It allowed them to try an onside kick. However, Brandon Lloyd recovered for the Patriots.
NOTES: Brady's 74.8 rating was his lowest of the season and his lowest since he had a 69.5 rating against Baltimore on Oct. 17, 2010. . . . Welker had the 28th 100-yard receiving game of his career with 103 on 12 receptions. He has 92 catches for the season and needs only eight more for five seasons with 100 catches, most in NFL history. . . . Brady threw only his fourth interception the season. . . . The Dolphins held the Patriots to 10 yards rushing in the first half. They last time they held a team to 10 yards rushing in first half was against Oakland on Nov. 28, 2010. . . . Dolphins left tackle Jake Long left the game in the first quarter with a triceps injury. Right tackle Jonathan Martin moved to left tackle, and Nate Garner played right tackle . . . Patriots left guard Dan Connolly left the game in the first quarter with a back injury. He was replaced by Nick McDonald.