All eyes will be on Sam Bradford as training camp kicks off

Sam Bradford is the Cardinals' starting quarterback, but rookie Josh Rosen will be waiting if injury strikes again. AP Photo/Matt York

The Arizona Cardinals open training camp on July 28 at University of Phoenix Stadium in Glendale, Arizona. Here's a closer look at the Cardinals' camp:

Top storyline: Sam Bradford's health and how it'll affect his availability will be the top storyline of Cardinals camp. His reps were limited in organized team activities but increased during minicamp. Coach Steve Wilks said multiple times this offseason that Bradford is the starter, but first-round pick Josh Rosen is being groomed to handle first-team snaps if needed. Bradford's injury history is well documented and one ailment could sideline him and thus thrust Rosen into the starting job.

QB depth chart: Bradford has been named the starter throughout the offseason by Wilks as long as he's healthy. What'll be intriguing to watch during training camp is how the backup reps are divided between Rosen and veteran Mike Glennon, who was signed as a free agent in March. There's a good chance Rosen could win the backup role and Arizona could end up either releasing Glennon or carrying three as an insurance policy in case Bradford goes down and Rosen struggles in his first NFL action.

Bubble watch: There are a handful of veterans on the bubble when training camp starts. Among them are Glennon, whose status could be affected by Rosen. However, the safe bet would be to keep Glennon on the roster so, if Bradford goes down, Arizona has two capable quarterbacks in Glennon and Rosen ready to play. Wide receiver Brice Butler is another player to watch on the bubble. He wants to be Arizona's No. 2 receiver, but a shaky offseason has that goal in question. A.Q. Shipley's job could be in jeopardy if rookie offensive lineman Mason Cole stands out during camp. Speaking of ...

This rookie could start: One of the position battles to watch in training camp involves a rookie who could win the job. Offensive lineman Mason Cole, Arizona's third-round pick out of Michigan, can push incumbent center A.Q. Shipley for the starting job. Cole hasn't missed a start in 104 games -- or the equivalent of eight years -- and has the experience and skill set to slide into the starting lineup.

David Johnson watch: The Cardinals' star running back wasn't at minicamp because he wanted a new contract. On Monday, Johnson and the team announced that Johnson would indeed report for training camp. However, Johnson will begin camp this season without a new deal.

CB2 next to P2: The cornerback job opposite of Patrick Peterson is still up for grabs heading into training camp, thus making it one of the top positions to follow. Arizona has brought in seven corners to compete for that job. But if one hasn't separated himself from the pack yet, how long will that take?