Although McGahee led the Broncos in rushing each of the past two seasons, the team's decision to invest two early-round picks at his position offered evidence that the 31 year old was on borrowed time.
But the timing of the move came as a bit of a shock.
"I was surprised that it would be this early, to be honest," Hillman said. "He's still capable of doing the things that he was doing six years ago."
But is McGahee capable of staying healthy?
After 10 seasons in the NFL with three teams -- including two with the Broncos that were plagued by late-season injuries as the wear and tear accumulated -- it was fair to wonder whether he could hold up any longer under a heavy burden if that need arose.
With Hillman and Ball earning praise from coaches and teammates for their growth in the offense and ability to pick up blitzes, and the presence of 2009 first-round pick Knowshon Moreno, who replaced the injured McGahee late in 2012, the potential of McGahee being a $3 million third-teamer was high. That price would have proved prohibitive, even with the team under the salary cap.
Still, the Broncos had no pressing reason to cut him so early. His contract wasn't crippling them under the salary cap; they still had room to sign their rookies and add multiple veterans, as they did last year with August signings of safety Jim Leonhard and linebacker Keith Brooking. McGahee could have been an insurance policy during the preseason, just as Moreno was in the regular season last year. So why cut him now?
"That's a good question," Broncos coach John Fox said. "I think in fairness to him, I think the things he's done for us, this gives him a better opportunity to hook on somewhere. It gives us a better opportunity to give some of these young guys more reps. It's just a conscious decision for us to get younger."
And it doesn't get much younger than this for the Broncos: Ball is 22 and Hillman, the youngest player in the NFL last season, is just 21.
"We joke around. We're starting to build a friendship," Hillman said. "He's a younger guy -- he's actually older than me, but I've been in the league longer, so I kind of help him out. He actually helps me out sometimes. He's coming along very well and he's doing a lot of good things out there."
When Fox employed running platoons, he typically opted to start the more experienced player. In Carolina, he started Stephen Davis over DeShaun Foster; Foster over DeAngelo Williams and finally Williams over Jonathan Stewart. The backup often had more carries, so if Fox follows form and starts Hillman over Ball, it doesn't mean that Ball will be relegated to spot duty.
Still, being the starter matters to both -- especially with the chance that Moreno, who started the last six games of 2012, could knock both out of that role.
"My goal is to play," Ball said. "Even if I get in and get one play, two plays, I'll be happy because I'm contributing in some way. Obviously, my goal is to be the starter, speaking for everybody, we want that position."
Who earns that role will depend more on their ability to pick up blitzes than carry the football. McGahee excelled in that area last year. Moreno improved after allowing a sack in Week 1. Hillman struggled, but believes that adding 20 pounds of weight to hit 200 pounds will help him.
The biggest question there is around Ball, who handled some pass protection at the University of Wisconsin when Russell Wilson was the starting quarterback in 2011, but faces a different challenge entirely in protecting Peyton Manning, who is nowhere near as likely to step out of the pocket and evade the pass rush.
Ball held up well in blitz pickup scenarios the last four weeks, but knows training camp will offer a sterner test.
"Well, right now with no pads on I think I'm pretty good. But, no, when we come back we're going to put pads on, it's going to be a different story," Ball said. "We're going to do pass protection scenarios one-on-one with the linebackers. But I'm sure I'll be good at it."
How good he is will determine whether the rookie can step into the void McGahee leaves.
Left tackle Ryan Clady was not on hand for minicamp, with his franchise tender still unsigned. Clady has indicated that he plans to sign the tender before training camp.
Clady wouldn't have been able to practice anyway because of his rehabilitation from postseason shoulder surgery, so in one respect the decision to leave the tender unsigned for now makes no difference. But it serves as a reminder of how Clady's status will linger over the team unless the parties agree on a long-term contract.
"At the end of the day, I know we want Ryan and Ryan wants to be here, so I'm convinced something good will happen," said Broncos coach John Fox.
With Clady out, Chris Clark took the snaps at left tackle during minicamp.
As usual, Broncos coach John Fox concluded minicamp by telling his players not to get in trouble during the next six weeks—although he refrained from offering his usual counsel, in which he tells players he doesn't want to read about them unless they won the lottery.
"I didn't want to use that one this year," Fox said. "I didn't want to wear that one out. I've still got the bye week for that."
Although the Broncos' 2013 season will be defined by their veterans, most of whom have a history of staying out of trouble, Fox still worries a bit about what might happen during the downtime.
"Any time you send that many guys off on their own for that period of time, you get a little nervous, to be quite honest with you," Fox said.
Some Broncos will return to team headquarters on their own before training camp. Linebacker Von Miller and running back Montee Ball both said they plan to come back before the end of June for workouts after taking two weeks off.
"(Strength coach Luke Richesson) was telling me if you could just come back you could work out with me," Miller said. "I was like, 'You know what, I don't have anything to lose coming here and working out with the guys, developing my body for a long season.'"
First-round defensive tackle Sylvester Williams is the only Broncos draft pick not under contract after Montee Ball and Kayvon Webster signed their deals less than two hours after the Broncos concluded minicamp.
Denver signed all of its third-day picks in May. The draft-slotting system means Williams is not expected to hold out. Denver hasn't had a training-camp holdout since Nate Irving was the last draft pick to sign his deal in 2011.
"The balls are just so accurate and you come out of your break and the ball is just there. It's almost like a long handoff sometimes. He definitely makes it easy on you."—WR Wes Welker, on Peyton Manning.
T Ryan Clady (tendered at $9.828 million).
(not tendered offers)
DT Justin Bannan (not tendered as UFA).
LB Keith Brooking (not tendered as UFA).
C Dan Koppen (not tendered as UFA).
WR Brandon Stokley (not tendered as UFA).
DT Ty Warren (not tendered as UFA).
RB Montee Ball (2/58): 4 yrs, terms unknown.
CB Kayvon Webster (3/90): 4 yrs, terms unknown.
DE Quanterus Smith (5/146): $2,352,000/4 YRS, $192,000 SB.
WR Tavarres King (5/161): $2,331,480/4 yrs, $171,480 SB.
T Vinston Painter (6/173): $2,277,932/4 yrs, $117,932 SB.
QB Zac Dysert (7/234): $2,208,200/4 yrs, $48,200 SB.
RB Lance Ball: RFA tendered at $1.323M with no compensation); $1.323M/1 yr.
S David Bruton: Potential UFA; $4.5M/3 yrs, $1.2M guaranteed.
CB Tony Carter: ERFA; terms unknown.
OT Chris Clark: RFA tendered at $1.323M with no compensation; $1.323M/1 yr.
P Britton Colquitt: RFA tendered at $1.323M with no compensation; $1.323M/1 yr.
DT Mitch Unrein: ERFA; $555,000/1 yr.
DT Kevin Vickerson: UFA; $5M/2 yrs, $1M guaranteed.
LB Stewart Bradley: FA Cardinals; $1.2M/1 yr, $300,000 guaranteed.
CB Quentin Jammer: UFA Chargers; 1 yr, terms unknown.
DT Terrance Knighton: UFA Jaguars; $4.5M/2 yrs, $500,000 guaranteed.
LB Shaun Phillips: UFA Chargers; $1M/1 yr.
CB Dominique Rodgers-Cromartie: UFA Eagles; $5M/1 yr, $5M guaranteed.
G Louis Vasquez: UFA Chargers; $23.5M/4 yrs, $5M SB/$13M guaranteed.
WR Wes Welker: UFA Patriots; $12M/2 yrs, $12M guaranteed/$6M fully guaranteed.
DE Elvis Dumervil (released).
FB Chris Gronkowski: Not tendered as RFA/Chargers; terms unknown
QB Caleb Hanie (released).
DE Jason Hunter: UFA Raiders; terms unknown.
S Jim Leonhard: UFA Saints; 1 yr, terms unknown.
RB Willis McGahee (released).
CB Tracy Porter: UFA Raiders; $2.5M/1 yr.
LB D.J. Williams (released).
WR Matt Willis: Not tendered as UFA/Lions; terms unknown.