The 49ers’ 90-man roster has taken shape, and camp battles are already developing on paper with organized team activities due to open May 20.

Some positions won’t have a lot of competition. Jimmy Garoppolo is locked in at the top of the depth chart. So are players like George Kittle and Dee Ford. Other spots will have a ton of competition based on the personnel on the roster going into OTAs. This is our seven-part series on the biggest roster battles we’ll have an eye on throughout the offseason.

The 49ers’ front office made a significant gamble this offseason with their decision to retain the entirety of the team’s group of safeties from last season. They re-signed Jimmie Ward and Antone Exum, and didn’t add any other veterans or draft picks at the position. That signaled a belief in the players on the depth chart at safety. It also sets up a potentially fierce battle at the position.

There may not be roster spots at stake, but the starting roles will certainly be up for grabs starting in OTAs. Here’s a look at perhaps the most important position battle on the 49ers’ roster through these offseason workouts.

The contenders

Sergio Estrada-USA TODAY Sports

Jimmie Ward – Year 6
Jaquiski Tartt – Year 4
Adrian Colbert – Year 3
Marcell Harris – Year 2
Antone Exum – Year 5
DJ Reed – Year 2