updated 9:43 p.m. ET Dec. 28, 2008

EAST RUTHERFORD, N.J. - Chad Pennington was in the opposing locker room at the stadium where he spent the first eight years of his career, a big smile peeking out from a gray Miami Dolphins "Division Champions" cap.

"It's always a sweet feeling to be a champion," the Dolphins quarterback said after beating the New York Jets 24-17 on Sunday. "That's what we are: AFC East champions. It's a great feeling. This organization has been unbelievable. They accepted me from the get-go. This has been an unbelievable ride."

And an improbable one at that.

Pennington, cut in the offseason by the Jets to make room for an aging Brett Favre, threw two touchdown passes against his former team and helped the Dolphins (11-5) complete a remarkable turnaround.

"It's not a revenge factor," Pennington said. "This week, being the 17th week, it was strictly focused on winning the championship, knowing that we controlled our own destiny. It just so happened that it had to come through New York. That's the only way fate would have it."

A year after going 1-15, the Dolphins joined the 1999 Indianapolis Colts as the only teams in NFL history to make 10-game improvements. Miami, under first-year coach Tony Sparano, has won five straight and nine of 10 in making the playoffs for the first time in seven seasons and winning its first AFC East title since 2000.

"I don't think words can describe it," running back Ronnie Brown said. "Earlier in the season, we could only imagine being in this situation."

Special feature NFL's top shots A look at the best photos from Week 17, including a somersault in Indy. NBCSports.com

And now, Miami (11-5) will host Baltimore (11-5) in the first round next Sunday.

"Around this time last year, we were going home with no return," receiver Ted Ginn Jr. said.

Meanwhile, Favre and the Jets (9-7) were left to wonder what happened to them — and what's to come.

After an 8-3 start and being mentioned as possible Super Bowl contenders with an NFL-high seven Pro Bowl selections, New York went into a tailspin by losing four of its last five — with Favre looking every bit a 39-year-old quarterback.

"The hardest part is the finality of it," Favre said, "especially when you expect to go on."

Whether Favre goes on remains to be seen. He said he'll have an MRI exam Monday on his ailing right shoulder, saying it would affect his decision on whether he'll come back for another season. Favre said he's been feeling discomfort in the shoulder for quite some time.

"It hurts in the back (of the shoulder), hurts down in the biceps and, occasionally, in my neck," he said. "Other than that, it's fine."

If this truly was it for Favre, who has yet to announce his plans, it wasn't a pretty ending. The 18-year veteran was 20-of-40 for 233 yards and a touchdown, but threw three interceptions.

It's also uncertain whether Jets coach Eric Mangini will return for a fourth season, although he said he thinks he will.

"We have never discussed it throughout the course of the season," he said," but that's my anticipation."

Meanwhile, Pennington, who went from the scrap heap to an MVP candidate, finished 22-of-30 for 200 yards and TD throws to Ginn and Anthony Fasano. Phillip Merling also returned an interception 29 yards for a score.

Video   Pennington downplays revenge Dec. 29: Dolphins QB Chad Pennington and coach Tony Sparano are elated to win the AFC East, while Jets QB Brett Favre and coach Eric Mangini search for answers. NBC Sports

"We were able to change this around with a good coach who came in with pride and passion," Ginn said. "We got a great quarterback and our D stepped up for us. That's all you could ask for."

The Jets took a 17-14 lead on Leon Washington's 10-yard touchdown run and a 2-point conversion early in the third quarter after taking advantage of a special teams mistake by the Dolphins. Punter Brandon Fields couldn't handle John Denney's high snap, and the ball bounced behind him before he fell on it at the Miami 28.

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