Caleb Williams is already a Bear.

He might also become a lone wolf.

NFL history was made in April when six quarterbacks were drafted within the first 12 picks of the first round: The Bears’ Williams (No. 1), Commanders’ Jayden Daniels (No. 2), Patriots’ Drake Maye (No. 3), Falcons’ Michael Penix Jr. (No. 8), Vikings’ J.J. McCarthy (No. 10) and Broncos’ Bo Nix (No. 12).

But how many members of that six-pack are going to be put on ice to begin their NFL careers?

Williams is the only coach-anointed starter entering training camp.

Penix, who was drafted just weeks after the Falcons signed Kirk Cousins to a four-year, $180 million free-agent contract, is the only near-certain backup.

The other four rookies are in winnable battles against veteran journeymen: Marcus Mariota (Commanders), Jacoby Brissett (Patriots), Sam Darnold (Vikings) and the duo of Zach Wilson and Jarrett Stidham (Broncos).

Teams must decide which developmental path is best: Let a rookie start from Week 1 if he is the best option and stick with him through tough times?

Or let him sit and learn behind a veteran for a few weeks?

There are plenty of arguments for and against which strategy works best.

Of course, the Penix-Cousins dynamic might be more interesting than any of those battles, given that the Falcons are a playoff contender, the 24-year-old Penix is considered ready to play by scouts and Cousins (who is coming off a torn Achilles) isn’t thrilled to have the future breathing down his neck before taking a snap.

The timeline for all these decisions will determine whether the face of NFL quarterbacking shifts gradually or all at once.

Here are nine other storylines to watch as all NFL training camps are open this week:

Contract disputes

Holdouts mostly are a thing of the past under a Collective Bargaining Agreement that doesn’t allow for forgiveness of $50,000-per-day fines.

Welcome to hold-ins, where a player unhappy with his contract reports to camp but doesn’t practice for one excuse or another.

Cowboys receiver CeeDee Lamb, 49ers receiver Brandon Ayiuk, Browns receiver Amari Cooper and Jets pass-rusher Haason Reddick all skipped mandatory minicamp and Saints running back Alvin Kamara left early — all to make a contract point.

Bengals receiver Tee Higgins can’t negotiate until after the season but might find ways to not push it while on the franchise tag.

As with everything, it’s bigger news if a quarterback does it.

The Dolphins’ Tua Tagovailoa is frustrated with his stalled negotiations and has a bigger reason to stage a hold-in than the Cowboys’ Dak Prescott, who can’t be tagged after the season if no deal is reached and thus is closer to free agency.

The Packers’ Jordan Love also is due an extension.

Bill of goods

The Bill Belichick-Patriots divorce is doubly intriguing.

First, what does camp look like in New England now?

Are players having fun?

Does new head coach Jerod Mayo actually provide insightful answers during news conferences?

What schematic changes are in store?

Second, Belichick won’t be on an NFL staff for the first time since 1974.

So, before he starts his new gig as an analyst on “Inside the NFL” beginning Aug. 30, where will he be?

Out-of-work coaches typically visit friends in other organizations during a gap year to broaden their perspective.

Knowing that Belichick plans to coach again in 2025, will anyone give the notorious rule-bender access to see their secrets in exchange for him lending his championship-winning expertise?

If Belichick is spotted at any camps, it will be a big story.

Looking at you, 49ers and Kyle Shanahan.

Harbaugh 2.0

Ten years after he and the 49ers parted ways over a power struggle, Jim Harbaugh is back in the NFL as the Chargers head coach after leading Michigan to the national title.

Will Harbaugh be more player friendly and delegate more responsibility the second time around?

If so, can he win that way at the same clip that he did with the 49ers (44-19-1)?

The biggest problem most college coaches have coming to the NFL is realizing grown men with big salaries don’t accept being beaten down and micromanaged like college kids.

The Chargers seem to be in the early stages of a roster teardown, but maybe Harbaugh finally can get the most of uber-talented quarterback Justin Herbert.

New York, New York and more

Aaron Rodgers (torn Achilles) and Daniel Jones (torn ACL) return to the Jets and Giants, respectively, after season-ending injuries.

Will both make it through training camp unscathed?

Tyrod Taylor moved from Jones’ backup to Rodgers’ backup for more money because the Jets can’t afford to have a playoff-caliber roster tank for the second straight year if Rodgers misses time.

Jones is the starter ahead of Drew Lock — no matter what Seahawks general manager Jon Schneider said — but might not have a long regular-season leash.

The Bengals’ Joe Burrow (wrist), Browns’ Deshaun Watson (shoulder), Colts’ Anthony Richardson (shoulder), Herbert (finger) and Cousins (Achilles) also are returning from season-ending injuries.

Chief concern

The two-time defending Super Bowl champions wish that their biggest “distraction” now was the Travis Kelce-Taylor Swift love affair that took over last season.

Since beating the 49ers in overtime, the Chiefs had four players arrested — three of whom (receiver Rashee Rice, left tackle Wanya Morris and backup offensive tackle Chukwuebuka Godrick) remain on the team.

Rice, the team’s No. 1 wideout, could be subject to a season-opening fine for his alleged involvement in a high-speed hit-and-run crash that resulted in eight criminal charges.

Kicker Harrison Butker is getting criticized by Serena Williams and made plenty of enemies with his controversial gender-role comments at a college graduation.

Oh, and the Chiefs have on-field question marks at key positions after parting with left tackle Donovan Smith and All-Pro cornerback L’Jarius Sneed while trying to accomplish the first-ever Super Bowl three-peat.

Mr. Unlimited’s last stand

Is Russell Wilson — aka “Mr. Unlimited” — finished?

The drop-off from his first nine Pro Bowl seasons with the Seahawks to his last two with the Broncos has been alarming.

Quarterback guru Sean Payton was willing to give him away for nothing.

The Steelers took a cheap flier on Wilson but backed him up with former Bears starter Justin Fields, setting up what could be the summer’s most-interesting training-camp battle … if head coach Mike Tomlin is open to it.

And if the Steelers don’t instead ask Fields to return kickoffs.

Wilson has “pole position,” Tomlin said, but Fields isn’t giving up that easy.

Wilson’s days as a starter are numbered if he doesn’t turn around his career now.

Trade chips

Aiyuk made a trade request that the 49ers are not inclined to meet.

Raiders receiver Davante Adams says he is staying put in one breath, then leaves the door open to a trade to the Jets (to reunite with Rodgers) in the next.

If quarterbacks Gardner Minshew and Aidan O’Connell are off the mark in training camp, could Adams try to force his way out of town?

Panthers running back Miles Sanders, Broncos receiver Courtland Sutton, Eagles cornerback James Bradberry and Patriots edge-rusher Matthew Judon are other big-name trade candidates.

Texans-Lions Super Bowl

Two years ago, you would have been laughed out of a sports bar for picking a Texans-Lions Super Bowl matchup.

Now? It’s sexy to pick the two teams that made the biggest jumps last season — even though they still have two of the seven-worst winning percentages of the 2000s.

The Lions enter camp with rejuvenated quarterback Jared Goff — armed with a new $212 million extension.

Is head coach Dan Campbell as convicted as ever to his radical strategies after a couple of risks cost the Lions key points in an NFC Championship game meltdown?

The Texans enter camp after spending $144.5 million in guaranteed money during the first three weeks of free agency, including trading for receiver Stefon Diggs, to meet heightened expectations.

Fly Eagles crash?

Be on the lookout for any signs of a hangover from the Eagles’ 1-6 finish — after a NFL-best 10-1 start — to last season.

Without the retired duo of franchise stalwarts Jason Kelce and Fletcher Cox to right the ship, the Eagles need new leadership.

Maybe it comes from Saquon Barkley, who is hungry to prove the Giants made a mistake letting him go and that running backs still can be worthy investments.

Head coach Nick Sirianni survived the chopping block, but it appears he still is as invested in tweaking opposing fans as fixing internal flaws.