Redskins running back Derrius Guice was hurt at the end of a 34-yard run in the first quarter that was negated by penalty. (John McDonnell/The Washington Post)

RICHMOND — Derrius Guice assured those around him that he was okay, believing the knee injury that had curtailed his first taste of preseason action would be nothing more than a brief setback en route to a dominant first year in the NFL. But by Friday afternoon, the Washington Redskins and their dynamic rookie running back learned the sobering truth: Guice is done for the year.

An MRI confirmed the offensive weapon, whom Redskins fans had pinned much of their hopes on, will miss the 2018 season because of a torn anterior cruciate ligament in his left knee.

Guice suffered the injury in the first quarter of Thursday night’s preseason-opening loss to the New England Patriots in Foxborough, Mass. And his first big gain showcased everything he was poised to bring to the Redskins’ offense — and everything Washington stands to lose in his absence: his burst, quick footwork, and impressive upper-body strength.

After shaking off some nervous energy, Guice took a handoff from quarterback Colt McCoy and rumbled 34 yards, spinning and stiff-arming his way downfield until he was tackled near the left sideline on a play that was negated by a holding penalty. The running back hyperextended his knee while being brought down to the ground by multiple defenders. But despite the limp in his gait, Guice, who was hampered by an injury to the same knee during his final season at LSU, was unaware of the extent of the damage done. And little did he know that his final stat line in their 26-17 loss — six carries for 19 yards — would be the extent of his 2018 production.

“I can walk fine,” Guice said in a brief interview session with reporters inside the visitors locker room at Gillette Stadium.

A day later, he was coming to terms with the fact that his rookie season was over before it ever really began. “God never makes mistakes,” he tweeted a short time later.

Guice’s injury is a devastating blow for a franchise that felt confident it had secured the steal of the April draft, selecting the former LSU playmaker in the second round, No. 59 overall. It’s also a critical blow for Jay Gruden, who returned this offseason with a retooled roster featuring Guice as a key piece in what appeared to be his best offensive unit in his five years as head coach.

Guice’s absence creates a void from a game-planning perspective and also from his connection with a community that had been craving a player with his unique blend of star power, relatability and playmaking ability.

He endeared himself to the fan base through his social media presence and regular interactions with fans, be it through his impromptu events, his live-stream video gaming, or the hours he spent signing autographs for fans long after practice had ended.

Guice quickly ingratiated himself in the Redskins’ locker room as well, and despite the competition among running backs for reps and roster spots, the group often stressed the brotherhood that existed among them.

“Had a tough time tryna hold back the tears this morning when I got the news,” tweeted Chris Thompson, who expected to power the Redskins’ rushing attack alongside Guice this season. Thompson was carted off the field with a fractured fibula in Week 11 against New Orleans. “We had something great going in our room but you know the squad got you every step of the way bro. Heal up and get ready to take over the league next year.”

The ACL tear is just the latest setback for the Louisiana native, who consistently has overcome seemingly insurmountable odds. Guice, whose father was murdered when he was 5, escaped his impoverished, crime-ridden Baton Rouge neighborhood and flourished at LSU. But despite being projected as a top 20 pick, he plummeted down the draft board amid unsubstantiated rumors and reports of character concerns.

Since arriving in Washington, Guice has been anything but trouble and had emerged as a potentially vital weapon in what the Redskins believe can be an explosive offense.

Washington had the fifth-worst rushing attack last season, averaging 90.5 yards. Rob Kelley, who also ended 2017 on injured reserve, figures to again be a big part of the Redskins’ rushing attack, along with Thompson. But there’s still a competition for the No. 1 job, per Gruden, and Kelley and Samaje Perine are competing with backups Kapri Bibbs, Byron Marshall and Martez Carter.

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