NAPA – Maxx Crosby is working hard under a ticking clock. The rookie edge rusher hasn’t been a Raider long, but knows he must be ready to contribute come Sept. 9.

That’s roughly a month from right now, when the Raiders open the 2019 regular season against Denver, and he’ll be counted on to hound Broncos quarteback Joe Flacco.

There’s no redshirt season for the fourth-round draft pick, no leniency for being a smaller-school prospect.

The fourth-round draft pick doesn’t have to be a finished product posthaste, but he has to be a functional member of a rotation off the edge. He knows it, and is busting his tail to be as prepared as possible for that big Monday night in Oakland.

Going from Eastern Michigan to the NFL is a big jump, one he’s preparing hard to make.

“In college, the playbook is simpler, and you get comfortable and you know what do. You might even have a redshirt year to prep, but in the NFL you have to play right now,” Crosby said after Friday’s practice. “That has been the main focus for me, to stay in the playbook, know what to do and focus on the details. That's something I'm still working on. You don’t have a year to get ready. You have to be ready to step right in the fire. That has been a point of emphasis.”

Crosby wants his debut and subsequent appearances to go well, so he’s trying to maximize every meeting moment and training-camp practice rep here in Napa.

“I like Maxx. Mad Maxx,” head coach Jon Gruden said. “You see us run gassers afterward, he beats everybody. His pursuit to the football has been incredible. He’s got a ways to go yet as a pass rusher, developing an inventory of moves and recognizing plays and situations, but nobody works harder. He might lead the league in effort, and that’s a hell of a compliment.”

That’s especially true coming from Gruden, who revs at high RPMs and is drawn to others who do the same.

Crosby has always operated with urgency in prep and game action. It’s his nature, and certainly helped him evolve from a string-bean pass rusher to a 266-pound NFL-caliber defensive lineman.

“It’s something that’s often overlooked,” Crosby said. “You look at guys like DeMarcus Lawrence and you see his sack numbers, but he works extremely hard behind the scenes to play so well.

“I’ve always been a guy who works hard and pushes himself, and that includes the gassers. I want to win every drill and in everything I do so, once the game comes, it’s easy.”

Crosby’s motor never stops during practice, and sometimes his relentless pursuit pays dividends. It has helped him get by mountain Trent Brown on occasion, and could be an asset on broken plays in games.

Crosby is also expanding his pass-rush repertoire this summer, but is focused on making a select few game ready.

“A lot of people think you need 10 moves to be somebody,” Crosby said. “I think having two or three moves you can do [perfectly] and be successful with is important. That’s what I have been working on, having moves ready and always being active and never giving up on a play and getting to the ball as much as I can.”

Crosby is around the ball a lot, and not just rushing the passer. Defensive coordinator Paul Guenther considers Crosby a "pleasant surprise," who can play the run a bit better than many expect. He has shown that, and some discipline to make plays as they come. He can obviously get after the quarterback. He also has a few pass deflections to his credit, and can chase down receivers in the flat. Athleticism allows for all that, which helped him thrive at lighter weights. He believes it will remain an asset now that he has bulked up.

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The Raiders wanted him attached to the strength staff this spring and summer, to gain the lean mass required to battle NFL offensive tackles and tight ends this season. That has happened, prepping Crosby for an NFL season's wear and tear.

“Coming out of college I was maybe 240. I weighed in this morning at 266,” Crosby said. “I have been doing everything I can and putting the right calories in my body so I can be ready for Sundays. They want me 260 plus, wherever I feel most comfortable. Honestly, I have been fluctuating around 265, so if I go up to 270, I feel like I’ll be fine.”