Former Maryland linebacker Demetrius Hartsfield, left, works out with trainer Tobe Stephens at the World Gym in Largod. After tearing his ACL midway through his senior season, he's trying to work his way back in order to make the NFL. (Marvin Joseph/The Washington Post)

Demetrius Hartsfield dropped onto the fitness center floor to stretch, first the hamstrings and then the groin. He hiked up his shorts and revealed a surgical scar on his left knee, fading into the skin and no wider than a pencil. Behind him, on a recent Friday morning at the World Gym in Upper Marlboro, trainer Tobe Stephens began barking orders.

“Five minutes on the elliptical,” Stephens said. “Resistance needs to be at eight.”

Nearly one year had passed since Hartsfield shredded the anterior cruciate ligament in his left knee, ending his senior season at Maryland and thus his college football career. But Hartsfield doesn’t think his playing days are over. The knee feels strong, and the motivation for every workout is to take another step toward reaching the NFL.

Hartsfield climbed onto the elliptical machine and began pumping his legs. Just below a bank of mirrors, a television showed highlights from a Thursday night game between the Carolina Panthers and the Tampa Bay Buccaneers. Hartsfield watches football broadcasts like a student. He follows the linebackers and studies their patterns. He feels close to his goal. Right now, nothing else matters.

The week before, Hartsfield flew to Wisconsin and worked out with the Green Bay Packers. Five other linebackers were there. They performed combine drills, like the broad jump and 40-yard dash. Last spring, Hartsfield’s sprint time clocked around 5.0 seconds. Yet as defensive coordinator Dom Capers watched, the stopwatch read 4.7. Afterward, Capers personally thanked Hartsfield for coming. He recognized the progress, but the Packers wanted someone to play right away.

“It was very bittersweet,” Hartsfield said later. “That’s the perfect word.”

Taking his time

After the NFL draft this spring, Hartsfield attracted little interest. Teams hedged at the torn ACL, unsure if the second-team all-ACC selection would be ready for summer workouts. But the Cleveland Browns offered Hartsfield a minicamp spot. His shot, it seemed, had arrived.

But Hartsfield declined. Close friend and San Francisco 49ers linebacker NaVorro Bowman convinced Hartsfield the speed of minicamp wasn’t the best place for someone at his stage of recovery. Besides, doctors hadn’t even cleared Hartsfield to play in pads.

“It really was the best decision,” Hartsfield’s mother, Tracy, said. “You can’t rush things. If they’re going to come, they’re going to come. And his time is coming.”

So Hartsfield continued to rehab, building strength in the knee and maintaining it in the rest of his body. He moved in with Stephens, an old family friend from Raleigh, N.C., and entrusted the 37-year-old fitness guru to guide him into the NFL.

Back at the fitness center, Hartsfield slid under the bench press bar, three 45-pound plates loaded onto each side. The total reached 315 pounds, roughly the size of an NFL offensive lineman. Hartsfield’s chest convulsed as he pumped out one repetition. Nearby, four workout partners watched with wide eyes. They, like Hartsfield, were once college stars too and, like him, still cling to bigger dreams.

“He makes that [stuff] look light,” one said.

Stephens knocked the weight down to 135. The abrupt change made Hartsfield’s muscles feel like jelly. He exhaled sharply, a single punctuated gasp. His technique was impeccable, but across the weight room, Stephens warned another client about failing form.

“Start getting tired, you start losing it,” he says. “That’s how you get injured.”

‘It’s been a tough road’

Or it happens like this: On Nov. 3, 2012, facing Georgia Tech and its triple option at Byrd Stadium in College Park, Hartsfield lined up at strong-side linebacker as he had all season en route to a team-high 78 tackles, despite playing just nine games.

Just before halftime, Hartsfield shook a block off the snap and turned into the backfield. Eyes trained on the quarterback and running back, Hartsfield never saw the fullback dive toward his knees, a technique known as the “cut block.”

Hartsfield doesn’t remember the pain after his knee absorbed the blow. He remembers lying on the ground, positive it was bad. He remembers walking off the field and into Gossett Team House, where he pedaled on an exercise bicycle and tried to assess the damage. Hartsfield even returned to the field and ran around on the sidelines. But when he cut, the pain came back.

Up in the stands, Tracy Hartsfield felt that sinking feeling of a mother’s intuition. Team protocol prohibited her from rushing to her son’s side, but she texted Craig Bennett soon after the injury happened. The team’s orthopedic surgeon responded within one minute. Two weeks later, he performed the operation and repaired the torn ligament.

But when Hartsfield spiked a fever shortly after New Year’s, he discovered the leg was infected, requiring another surgery and daily treatment for the next eight weeks.

“It’s been a tough road,” he says today.

Things are looking up now. Stephens forces Hartsfield to watch film in his house, to remain mentally fresh. They sneak in extra workouts whenever possible, like the time Hartsfield did pull-ups on a nearby jungle gym after Stephens dropped his two kids off for soccer practice. Stephens, who played college basketball at North Carolina Central for two years, knows what professional sports require. This year alone, he trained NBA draft picks Victor Oladipo, Erick Green and Dennis Schroeder.

“Will Meat make it?” Stephens asked. “Oh yeah. Most definitely.”

He watched as Hartsfield dropped into a push-up position, hopped up and caught the medicine ball launched at his face by another trainer. Hartsfield spends three days each week here at World Gym, then three more days either in an aquatics center or on the field in nearby Landover, strengthening his pass-rush technique in the shadows of FedEx Field.

The workout ended, an hour and a half after Hartsfield first arrived. He slipped into sandals and slung a backpack over both shoulders. He fiddled with the white drawstring on his sweatpants and smiled.

“Everything’s coming together,” he said. “I’m just happy.”

As he left, he snuck a glance at the televisions, where the NFL highlights continued to play.