RENTON, Wash. -- If you've followed the NFL long enough, you've read a story or 10 about a player who reported to training camp in the best shape of his career.

You've also read about the former first-round pick who's trying to finally live up to expectations ... about the injury-prone player who will make a big impact as long as he can stay healthy ... the potential "one-two punch" at running back.

And no training camp would be complete without a piece on the pending free agent who hopes to set himself up for a big payday -- but who's supposedly not worried about his contractual future.

Rashaad Penny is all of those obligatory August storylines wrapped into one. And as cliché as it sounds, he's among the Seattle Seahawks' more intriguing players heading into the 2021 season because of it, even as he prepares to again serve as their RB2 behind Chris Carson.

"Rashaad came back at 225," coach Pete Carroll said glowingly on the first day of camp. "He looks great. He worked out here all throughout the offseason and it really paid off.

"Best he's looked since we've seen him."

Penny didn't practice during minicamp while continuing to recover from a cleanup procedure on his left knee, the one he previously had surgically repaired. That's why it was a bit unexpected when he hit the ground running -- fast -- at the start of training camp. His trimmer frame has been evident, as has his speed on a few breakaway runs.

Penny previously said he weighed around 238 pounds as a rookie in 2018. He got down to 230 during the 2019 season with the help of a nutritionist and a cleaner diet. After tearing his ACL that December, he used the year-long recovery period as an opportunity for self-reflection and realized he needed to further improve his body.

Penny trained with fellow Seahawks running back Travis Homer in Seattle this offseason instead of back home in Los Angeles, which he called the best decision of his career. He began camp at 223 pounds and knows he has to work to stay there.

"This is the lightest I've ever been," he said. "I feel very explosive and honestly feel like I'm back in high school again. I feel way faster."

A trimmer, faster Penny looked as though he was starting to emerge in the second half of 2019. His 236 all-purpose yards and three touchdowns over a two-game stretch was the best glimpse to date of why Seattle took him in the first round. But then came his ACL tear, continuing a run of injuries that the Seahawks never saw coming.

He missed three games earlier in the year (hamstring) and two more as a rookie (knee) as well as most of the 2018 preseason (finger). All told, Penny has played in only 27 of a possible 48 regular-season games, including just three late last season once he came back from reconstructive knee surgery.

Go figure that when the Seahawks were scouting Penny ahead of the 2018 draft, they gave him the highest medical grade they had ever given to a prospect. It was among the reasons why they took him 27th overall over Nick Chubb, whose success with the Cleveland Browns has made that decision all the more regrettable.

While Chubb is celebrating a recent extension after a second straight Pro Bowl season, Penny is heading into a contract year since Seattle declined his fifth-year option in May. That was the widely expected outcome given the price (a fully-guaranteed $4.523 million), Penny's injury history, underwhelming production (823 rushing yards in three seasons) and the fact that Seattle had just re-signed Carson.

"I never focus on any of that," Penny said early in camp. "I'm just happy to be available ..."

That was before he missed Saturday’s practice and the Seahawks' mock game Sunday. Carroll said they were merely being cautious with a minor thigh issue and that Penny felt fine when he ran.

Carroll has described the offense Seattle is installing under new coordinator Shane Waldron as running back-friendly. Penny sees plenty of similarities to the one he played in at San Diego State, where he led FBS in 2017 with 2,248 rushing yards and ranked second with 23 rushing touchdowns.

"It's the same exact playbook," he said hyperbolically. "It's nothing different than what I did. I love the perimeter game, they love to get me on the outside and that's the majority of what this playbook is. Then to open up the pass game with the talented receivers we have and trying to create a one-two punch with Chris. That's the biggest thing and we've got a lot of great running backs, so I think it fits me very well."

In theory, Penny's home-run ability is the ideal complement to Carson's powerful style. With Carson battling his own injury issues throughout his career, the Seahawks have only had both backs healthy and producing at the same time for a few brief spurts.

"Chris is really the starter for us," Carroll said. "He has been and has established that. But when Rashaad's out there, we think he's just as likely to break it as anybody. We're really hoping that those two guys battle it out, and whatever happens, happens. The more Rashaad plays, I think the better that makes Chris. Chris has been a marvelous player for us, and Rashaad's got to prove some stuff.

"He's got to prove that he's back, and that he can stay out there and stay durable and all that. That's what's at hand right now. But we do know that Rashaad has big-play ability, and we love it coming in off the bench and however we mix it up."

While marveling again at Penny's fitness, Carroll joked that he must have been trying to keep up with Carson, who shows off his chiseled physique when he posts pictures and videos of his offseason workouts.

"Just look at Rashaad's conditioning," Carroll said. "He probably saw the same clips of Chris all summer long and so he matched him. The one-two punch between those guys could be really explosive for us."

Cliché, but true.