Why did Arizona cut its presumptive starting QB? Everything you need to know about what's next

TEMPE, Ariz. -- There's never a dull moment in the NFL. The Arizona Cardinals made sure of that Monday.

A day before teams are required to reduce their rosters to 53 players -- and less than two weeks until the Cardinals play at the Washington Commanders in Week 1 -- Arizona made waves when it cut veteran quarterback and presumptive starter Colt McCoy. Also on Monday, Cardinals coach Jonathan Gannon said Kyler Murray, who has been out since December after tearing the ACL in right knee, will start the regular season on the physically unable to perform list, meaning he'll miss at least the first four games.

That leaves the Cardinals to choose between Joshua Dobbs -- whom Arizona just acquired from the Cleveland Browns in a trade Thursday -- or fifth-round rookie Clayton Tune as their starting quarterback. However, the Cardinals will wait as long as they can to reveal their chosen starter.

"I'm not going to name a starter because I think it's a competitive advantage for us going to Washington," Gannon said. "But, we'll know who the starter is."

Why did the Cardinals make these moves, and what's next?

McCoy, who played in 12 games for the Cardinals over the past two seasons, wasn't let go because of something he didn't show the staff, according to Gannon. All the head coach would tell reporters Monday is that Arizona's decision-makers looked at McCoy's "full body of work" -- from OTAs to minicamp to training camp to the preseason -- and believed the best decision was to move forward without him.

Gannon also mentioned production played a part in the decision to release McCoy, who's soon to be 37.

McCoy's lack of mobility might have worked against him; Gannon pointed to that trait as one of things he liked about Dobbs. McCoy also dealt with an elbow injury in camp, and Gannon limited McCoy's throwing to, essentially, every other day in an effort to preserve McCoy's arm. But in the past couple of weeks, McCoy's arm looked live and capable.

Tune has been around the Cardinals' new offense since May. So he has been learning and growing into it just as everyone else, regardless of experience, has been around him. All of those reps in the scheme, and there have been hundreds this offseason, have given him the type of instinct in the offense that only comes with time.

"Generally, there's that belief that more reps are better for a young guy," offensive coordinator Drew Petzing said. "I think there's certainly some truth to that."

Tune looks to be improving every day and has been open about knowing how to fix mistakes when they arise. He has also shown a live arm and the ability to scramble, which has caught Gannon's attention. Tune said he's a capable and willing scrambler -- he rushed for 1,253 yards over five seasons for the Houston Cougars -- but that it's not a large part of his game.

"I like that he plays fast," Gannon said. "He has command when he walks into the huddle. You see the arm talent. So, he's got a long way to go, just like everybody does, but he's doing a good job."

Tune, who was drafted 139th overall, would be the first quarterback drafted in the fourth round or later to start a season opener since Dak Prescott, who went 135th in 2016. Tune would also be the latest drafted quarterback to start a season opener as a rookie since Randy Hedberg (No. 196) in 1977.

There's the obvious answer: He's a rookie. Is it valid? Maybe. But the lack of experience could be the argument not to start Tune, especially coming from a college system that didn't run a pro-style offense, which is what the Cardinals are running now.

"There's also a lot of value in sitting back and watching guys do it, who have done it at a high level, who really understand the game," Petzing said. "And he's done a great job, I think, of balancing the two."

There are parts of his game that still need fine-tuning -- no pun intended -- and to throw him into the fire as a rookie could be a major risk, both in the short and long term. There were a handful of throws during the preseason and training camp that would have been easy completions if he hadn't sailed them. If Tune does that in a game, it could be the difference between a first down and a pick-six.

Dobbs has experience learning an offense similar to what the Cardinals are running now. He spent part of the 2022 season in Cleveland, where Petzing was the quarterbacks coach and Israel Woolfork, who's now the Cardinals' quarterbacks coach, was a coaching fellow -- experience that Gannon called "valuable."

"I think just his familiarity of the system, the verbiage, those two guys that are really the main guys coaching [Dobbs]," Gannon said. "I think that obviously helps him a lot."

Beyond his time with Petzing and Woolfork, Dobbs actually has NFL experience -- albeit not much. He has played in eight games in six seasons, including two starts last season with the Tennessee Titans, when he threw for 232 and 179 yards in two losses. Dobbs also has the type of skill set that Gannon wants in his first quarterback as a head coach.

"He is a mobile guy that understands the system, but he is a mobile guy that can make throws and play in the pocket and play outside of the pocket," Gannon said. "So, that's what we're looking for."

Yes, he knows the two most important coaches and, yes, there is some carryover from the Browns' offense he learned to what's being run in Arizona, but Dobbs hasn't taken a snap with the Cardinals yet. He'll likely get his first snap in a walk-through Tuesday and then his first real practice snaps Wednesday, but he doesn't have any experience working with center Hjalte Froholdt and the rest of the offensive line, nor has he developed timing with the wide receivers and tight ends.

"It's never easy for a new guy coming to a new team, but he is familiar with the system, he's familiar with Drew and Izz and we feel good where he is at with that," Gannon said.

Who starts Week 1 doesn't mean anything for Murray. Unless the team gets off to an extraordinary start, he'll return to being QB1 when he's healthy.

It's a different story for the Cardinals' season, however. Arizona has been committed to a rebuild all offseason, and the decision to move on from McCoy and start either Dobbs or Tune continues with that. There will be a learning curve regardless who's under center. With Dobbs, it'll be getting adjusted to a new offense and new teammates. With Tune, it'll be adjusting to NFL football.