Follow CBSMIAMI.COM: Facebook | Twitter

DAVIE (CBSMiami/AP) — It’s taken nearly two decades but the Miami Dolphins think they have finally found their next franchise quarterback.

READ MORE: ‘Try To Take Our Guns And You’ll Learn,’ Florida Lawmaker Tweets At President Biden

When Ryan Tannehill agreed to a four-year extension with Miami, the quarterback’s agent told him that at some point, “you might regret this deal.”

It’s not that Pat Dye Jr. isn’t pleased with his client’s six-year, $96 million extension, which includes $45 million guaranteed and $77.7 million of “new money.” He’s just convinced the Dolphins got great value with the deal that lasts through 2020.

Dye believes Tannehill’s worth will be considerably higher by the end of this contract.

“It’s always a dream to sign a big contract, but the main dream is winning a championship and holding that trophy up with your teammates,” said Tannehill, who was Flanked by Dolphins general manager Dennis Hickey and head coach Joe Philbin on Tuesday as he talked about the deal.

The ink is barely dry on the deal, but Dye told Hickey, “We’re going to be knocking on the door in three or four years” to renegotiate.

Tannehill believes he’s a championship-caliber quarterback.

“That’s why I’m here, is to win championships,” Tannehill said. “If I wasn’t that, if these guys didn’t believe in me, then I wouldn’t be sitting in this chair.

“I don’t measure myself up against (Dan Marino), but at the same time, I’d love to have a career that stands up to his, and ultimately, I want to win championships.”

Dye said Dolphins owner Stephen Ross met with Tannehill before the NFL Combine for lunch, during which Ross told him, “You’re our guy and we’re going to do this deal.”

READ MORE: Broward Sheriff Tony, School Superintendent Cartwright Implement Enhance Safety Measures In Light Of Texas Shooting

Still, Dye said he wasn’t optimistic three weeks ago that a deal would get done. That changed last Monday, when the Dolphins improved their offer. The contract was finalized a week later.

“I didn’t know if it was going to happen or not. I still had two years left on the (previous) deal. It wasn’t something I was expecting,” said Tannehill, whose wife, Lauren, and parents, Tim and Cheryl, also were in attendance on Tuesday. “Once they came to me and wanted to talk I was super excited to try to get something done.”

Tannehill is the first quarterback from the 2012 draft class, which also included Andrew Luck, Robert Griffin III and Russell Wilson, to receive an extension.

The Dolphins QB had career-best numbers in his third NFL season last year, throwing for 4,045 yards and 27 touchdowns with a passer rating of 92.8.

“I’ve watched him get better every year,” Philbin said. “I think that trend is going to continue.”

Said Hickey: “We couldn’t be more happy and pleased to have him as our quarterback for the present and for the long-term.”

Unlike Luck, Griffin III and Wilson, Tannehill has yet to reach the playoffs. But he said Tuesday the Dolphins “have all the pieces we need to have a special 2015.”

Tannehill said he understands “the ultimate factor in judging quarterbacks is winning games.”

He added that despite the added pressure that will come with his new contract, his approach and preparation won’t change.

“He believes in himself,” Dye said. “I do think he has the makeup and ingredients to be special. He’s had special moments. We’ve seen it.”

MORE NEWS: Car Slammed Into Miami Home, Three Dead, Two Hospitalized

(TM and © Copyright 2015 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2015 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)