Ryan Tannehill's final drive an encouraging sign for Dolphins

Ryan Tannehill was one failed drive away from hearing a work's worth of criticism.
After a mediocre preseason debut in Miami's preseason opener, and a four-interception day last Tuesday in practice, the Dolphins quarterback looked really crummy to start his team's 27-3 win Friday night at Jacksonville. But Tannehill then redeemed himself with an impressive touchdown drive.
So Dolphins fans can exhale a bit. Tannehill's encouraging drive heads up five observations from Friday's game:
1. Tannehill went 2 of 5 for just 11 yards in last Sunday's 24-20 loss to Dallas. And he was just 2 of 5 for 23 yards on his first three drives Friday, which produced a total of just one first down.
But Tannehill then caught fire on his final drive before taking the rest of the night off. He completed 3 of 4 passes for 52 yards while leading the Dolphins 80 yards for a 7-0 lead. The drive culminated with Tannehill throwing a 22-yard touchdown pass to tight end Dustin Keller.
Tannehill finished 5 of 9 for 75 yards. He was playing his first game with speedy wide receiver Mike Wallace, who missed the opener due to a groin strain, but Wallace never had the ball thrown his way.
Tannehill spent plenty of the first three drives running for his life. There are concerns about the first-string offensive line, and Friday's game didn't do a lot to eliminate them.
2. While receivers Wallace and Brandon Gibson got a lot of headlines when they were signed in free agency, don't forget about newcomer Keller.
Keller looks like he could become Tannehill's favorite target. In addition to the touchdown catch, he also had a nifty 14-yard grab from Tannehill to finish the night with two catches for 36 yards.
Keller led the New York Jets two years ago in receiving with 65 grabs. It wouldn't be a surprise if Keller leads the Dolphins in catches this season. With Wallace stretching the defense and Gibson and Brian Hartline getting plenty of attention on the outside, Keller figures to be open plenty in the middle of the field.
3. We've got a running back battle again.
Lamar Miller was the more impressive runner in the first preseason game. But Daniel Thomas was the better back against the Jaguars.
While Miller started and gained just six yards on two carries, Thomas had 19 yards on four carries, including a strong nine-yard burst. Miller also dropped a pass.
Miller remains the favorite to win the battle. But Thomas is showing he's not planning to give up without a fight.
4. Cornerback Nolan Carroll hasn't been overwhelming in training camp. His last practice before Friday's game included being beaten by Wallace on Wednesday on a 40-yard touchdown pass.
But Carroll stepped up Friday. He had an interception on the final play of the first quarter off a deflected ball and returned it 22 yards
The Dolphins didn't force any turnovers against Dallas. But they got four against the Jaguars, two fumble recoveries and rookie cornerback Will Davis also getting an interception.
Carroll isn't going to start due to the Dolphins looking strong on the corners with Brent Grimes and Richard Marshall. But he was solid Friday, as was just about everybody on Miami's defense.
5. The battle at kicker just got very interesting.
Incumbent Dan Carpenter looked good in the preseason opener, making both of his field-goal attempts and both of his extra points. Then it was the turn Friday for rookie Caleb Sturgis, a fifth-round pick from Florida.
What a debut it was. Sturgis made both his field-goal attempts, one from 58 yards and the other from 36, and hit all three of his extra points. The 58-yarder cleared the crossbar easily.
While Carpenter has more experience, Sturgis has the stronger leg, which he also showed on kickoffs. And he makes $400,000, more than $2 million less than Carpenter's $2.7 million. If all is equal, it wouldn't be a surprise if the Dolphins go with Sturgis.
Chris Tomasson can be reached at christomasson@hotmail.com
or on Twitter @christomasson.