Will Ryan Tannehill's numbers continue to rise?

DAVIE, Fla. -- Here was a big selling point for the Miami Dolphins to give starting quarterback Ryan Tannehill a $96 million contract extension this week: His numbers improved in each of his three seasons.

The Dolphins view Tannehill, 26, as an ascending player. In their view Tannehill hasn't reached his ceiling, which is why they are confident their six-year contract with $45 million in guarantees will be worth the investment.

"The biggest thing that I've been excited about is, I've seen the development with Ryan over a period of three years," Dolphins head coach Joe Philbin said. "I think he has great potential, I'm fully confident that he's going to get better and better and better, that's what I'm really excited about."

But there are risks involved. What if Tannehill's numbers do not improve in Year 4?

Tannehill had a career year in 2014 with 4,045 yards, 66.4 completion percentage, 27 touchdowns and a 92.8 passer rating. Those will not be easy numbers to top.

Tannehill must be at his best consistently for Miami to end its six-year playoff drought. There are several areas where he must improve: his deep ball, holding the ball too long at times and fourth-quarter performance among others.

Another challenge will be jelling with new receivers. Both of Miami's starting receivers from 2014 -- Mike Wallace and Brian Hartline -- are gone. So are starting tight end Charles Clay and key backup Brandon Gibson. The Dolphins acquired wide receiver Kenny Stills in a trade with the New Orleans Saints to replace Wallace's speed. They also drafted first-round pick DeVante Parker and signed veterans Greg Jennings and Jordan Cameron.

"Obviously it's a challenge to get on the same page," Tannehill admitted. "It's been great to work with those guys starting back in March on our own and now once the offseason program started. Seeing those guys improve with our route concepts, the way we run routes, being able to coach those guys through the process, has been really fun for me."

The Dolphins need Tannehill to develop into a star more than ever. The big contract only adds to the pressure at Miami's quarterback position.