Rob Carr, File, Associated Press
FILE - In this Sept. 9, 2010, file photo, Maryland linebacker Demetrius Hartsfield watches from the sideline during the second half of an NCAA college football game against Florida International in College Park, Md. Hartsfield is affectionately called "Meat" by his coaches and teammates. To opposing quarterbacks, he's simply dangerous _ and a big reason why the Terrapins are ranked seventh in the nation in total defense.

COLLEGE PARK, Md. — It's no accident that Maryland linebacker Demetrius Hartsfield leads the nation's seventh-ranked defense in tackles and sacks.

Hartsfield — affectionately called "Meat" by his coaches and teammates — works hard on the practice field and in the weight room. He also spends hours each week studying film.

"I've learned that how you practice and how you prepare is how you play," Hartsfield said Tuesday. "As a young player you don't really understand that. It's crazy, because I've been told that since high school. But I don't think I realized that until end of my sophomore year here."

Hartsfield was honorable mention All-ACC last year, and this season he's playing even better. The 6-foot-2, 240-pounder has 43 tackles and three sacks for a unit that is allowing only 257.2 yards per game.

Hartsfield and the defense are a big reason why the Terrapins (3-2, 1-0 Atlantic Coast Conference) already have exceeded last year's win total.

"He studies the game," coach Randy Edsall said. "He'll put the time and effort into watching film. He wants to be good. I think that's one of the things that's very important. I can see a big difference in him from last year in the knowledge and the confidence that he has been playing with."

Hartsfield had 10 tackles in Saturday's 19-14 win over Wake Forest and sealed the victory with a fourth-down sack. After downing Demon Deacons quarterback Tanner Price on a fourth-and-15 with under a minute left, he celebrated the accomplishment with a display borrowed from teammate A.J. Francis.

"He had the gall to steal my sack dance," Francis said. "After we stopped Wake at the goal line earlier, I was making fun about of how he does this high step off the field like he's Deion Sanders. So after the sack, he does his high step and then my sack dance."

Hartsfield laughed when told of Francis' assertion.

"The only reason I did it is because he told me he was going to steal my celebration," Hartsfield said. "So I stole his."

Hartsfield had more reason to celebrate this week, because his performance against Wake Forest earned him honors as ACC linebacker of the week.

Off the field, Hartsfield also has an impressive resume. The fifth-year senior already has his diploma in criminal justice and is furthering his education this semester.

"God willing, I plan on playing in the NFL," he said. "The backup plan is helping juveniles."

Edsall describes Hartsfield as "a great guy to be around but quiet. He never gets too high, never gets too low. Very steady."

Hartsfield's demeanor takes a radical turn on game day.

"The majority of the time I'm pretty laid back," he said. "But my teammates know I'm a jokester, wild and crazy. On the field, I'm nasty, I talk junk the whole game."

The next challenge for Hartsfield and Maryland comes Saturday at Virginia (2-4, 0-2). Coming into the game, the Terrapins rank second in the ACC in total defense behind only Florida State.

"Yeah, but they played two easy teams (Murray State and Savannah State)," Hartsfield said. "I think we're in a good position to overtake them and become the No. 1 defense in the ACC."