DAVIE, Fla. (AP) - Matt Moore has been through this before.

While with Carolina in 2009, Moore was called on to replace injured starter Jake Delhomme for the last five games of the season and went 4-1 with eight touchdown passes and only one interception.

The next April, Carolina drafted quarterback Jimmy Clausen in the second round and added Tony Pike in the sixth round.

Last season, Moore began as the backup to Chad Henne with the Miami Dolphins before Henne went down with a shoulder injury. After struggling in his first four starts, Moore was 6-3 in the last nine games, and his passer rating of 97.8 was the sixth-best in the league during that span.

But general manager Jeff Ireland made it clear after what was overall a disappointing 2011 season that his team needed to get better at the position, and he did his part in the offseason to address the problem.

"Jeff Ireland was very clear with me that they were going to go after somebody, if not two guys, which they did," Moore said. "So there were no surprises there, which is appreciated. You've got to go out and do your best and do your job and you can't worry about the transactions that are being made because that's out of your control."

Before the draft, Ireland signed longtime Jacksonville starter David Garrard to join Moore. Ireland then made Ryan Tannehill the first quarterback drafted in the first round by Miami since 1983.

Now, it's time to decide which of these three will be the starter.

"These guys are real professionals," first-year coach Joe Philbin said. "They are all a little bit different guys, which is good. Beyond that, we're kind of letting this training camp bring out the best in each one of them and hopefully we can see and come to a good decision as we move forward."

Philbin said in the spring he was hoping to settle on a starter by the third preseason game, which is Aug. 24.

While Tannehill missed the first two days of training camp before signing his rookie contract, Moore and Garrard took turns working with the first-team offense. Offensive coordinator Mike Sherman, who coached Tannehill at Texas A&M, said the rookie would get his turn with the No. 1 offense soon.

The battle for the job is one of the most heated in the NFL this summer, and it's being waged under the ever-present "Hard Knocks" cameras.

"I know a lot has been written and there has been a lot of speculation about who is ahead, and whether this guy is behind and he's not ready, but that is news to me," Philbin said. "We are still evaluating all quarterbacks, Pat Devlin included, and we'll make a decision when it becomes evident."

Whoever wins the position will become the seventh different quarterback to start the opener for the Dolphins since Dan Marino retired.

Garrard joined the Dolphins after sitting out all of last season. The Jaguars' starting quarterback for five seasons, he was released days before the 2011 opener and later underwent back surgery.

The wild card in the Dolphins' quarterback battle is Tannehill.

He was taken in the first round with the idea he would be Miami's starting quarterback for many years, but it's unclear exactly when the Dolphins want to put him in the lineup.

Tannehill does have the advantage of having played in Sherman's offense at Texas A&M, but he also started only 19 games after beginning his college career as a wide receiver.

"I feel like I'm in it," Tannehill said. "I may be naive, but the coaches haven't given me any indication that I'm not, so I'm going to go out there every day and do my best to get better every day and hopefully win the job."