The Vikings begin reporting to the first training camp July 24 at the TCO Performance Center in Eagan. The first full-team practice is July 28. Check here for new details on tickets, parking and times.

Before then, the Star Tribune will take a look at each position group. Sunday: Running backs.

On the 90-man roster: 7 running backs

Locks: Dalvin Cook, Latavius Murray

On the bubble: C.J. Ham, Mack Brown, Mike Boone

Practice squad candidates: Roc Thomas, Johnny Stanton

Changes
(+) Restructured Latavius Murray's contract, saving more than $1 million in cap space while allowing Murray to become a free agent after the season. … Signed three UDFAs in Boone (Cincinnati), Thomas (Jacksonville State) and Stanton (UNLV).

(-) Jerick McKinnon signed a four-year, $30 million contract with the 49ers, including $11.7 million guaranteed at signing.

Situation
Cook, the Vikings' workhorse, enters camp with both his ongoing rehab and a reworked offense to think about. Movement, screens and space are common descriptors for first-year coordinator John DeFilippo's touch on the offense. Cook is still in the type of system he feels most comfortable, which is predicated on zone blocking and allowing his superb vision to take over. A critical move, because of Cook's recovery and short-yardage situations, was retaining Murray. The veteran improved throughout his first season with the Vikings and Murray will still play a role regardless of Cook's health.

"Coach Flip just wants to get guys in space, get them the ball and let them make plays," Cook said. "He just wants us to run free. There's a lot of green grass for everybody on the field to run."

Top question
Will there be any need to hold back Cook? His rehab from a torn ACL is on schedule, returning to team drills this spring about 8.5 months after surgery. Indications are he could be near full go for training camp, however head coach Mike Zimmer is eager to see him in pads and around live contact again. The Vikings don't want to overdue it too soon with Cook, keeping the focus on Week 1 against the 49ers.

"It's about getting him around bodies flying around him a little bit," Zimmer said. "It's not so much trying to figure out what he can do right now; we're trying to get him comfortable with 22 players around him."

What you should know
The Eagles didn't use a fullback in two years with John DeFilippo on staff as quarterbacks coach. The Browns sparingly used the position when DeFilippo was coordinator in 2015. So what kind of role can C.J. Ham play in this Vikings offense? He returned to his roots, playing more running back this spring with the third-team offense. Ham caught seven passes for 68 yards last season, his first as a contributor.

Notable number
70 percent — This wasn't a running back by committee before Cook's knee injury in Week 4. The Vikings played Cook about seven of every 10 plays, making clear their commitment to a dynamic talent. His reps will be monitored in the preseason. Should Cook's initial reps and continued rehab look good, there's no reason to think he won't again become a No. 1 option in the offense.

Top competition
No. 3 running back — McKinnon entered last season as the Vikings' third backfield option and ultimately played an integral role in the offense. The preseason could offer surprises from a relatively unproven group in Ham, Brown, Boone and Thomas.