Ask defensive end DeMarcus Lawrence about the Dallas Cowboys' pass-rush drill and don't be surprised if the Pro Bowler mentions the time it interfered with him kissing his girlfriend.

"La'el [Collins] busted my lip, and I went home to see my girl and kid, and my girl was like, 'What's wrong with your lip?' So I showed her, and she was like, 'Eww, don’t kiss me,'" Lawrence said. "So it kind of made me mad, and I had to whup all their asses because somebody busted my lip."

In the one-on-one drill later that day, Lawrence took on four of the five Cowboys’ starting offensive linemen one snap after the next.

"I started on the right side with Tyron [Smith]. Did him once," Lawrence said. "Then Connor [Williams]. Went against him twice because my move was s---ty the first one. Then I went against Travis [Frederick], and I skipped Zack [Martin]. I ended it with La'el."

Rod Marinelli has been coaching NFL defensive linemen since 1996. He has coached a Pro Football Hall of Famer in Warren Sapp and a future Hall of Famer in DeMarcus Ware. He has coached a lot of quality defensive ends, from Simeon Rice to Julius Peppers to Lawrence, who had 14.5 sacks last year and made the Pro Bowl.

Lawrence's march through the line brought a smile to the face of the old-school coach.

"I saw old Peppers do it: 'OK, I got you. I got you. I got you,'" Marinelli said. "That's fun to watch. He just loves the pass rush. He loves to play."

In training camp, nothing gets livelier than the one-on-one-pass rush drills.

Tucked into a corner of the practice field, the offensive linemen stand on one side and the defensive linemen stand on the other. In between are the combatants. The left tackle lines up next to the guard and center, so there is some semblance of reality to where the pass-rusher can't take unreasonable routes to the "quarterback," who is normally an equipment room intern. Across the way is the defensive end.

Offensive line coach Paul Alexander stands behind the defensive lineman so as to not give away the snap count. To his left or right stands Marinelli. At the snap, the offensive lineman drops into a pass set. The defensive lineman charges at him either using a spin move (Taco Charlton's favorite) or power (Tyrone Crawford's favorite). Lawrence can blend the finesse and the power.

At best, each snap lasts three seconds. Sometimes the coach will wait to blow the whistle to signal the end of the play.

"You feel it, don't you?" Marinelli said of the energy, his eyes lighting up as if he is in his 20s and not a few weeks beyond his 69th birthday. "Competing our living asses off, man. Because you have to. Man, there's three All-Pro players there, and the right tackle is pretty doggone good. And that young left guard, he's going to be something. So I mean, it's every down. If you want to show me something, you'd better work on these guys."

Of the handful of training camp fights while in Oxnard, California, three of them came during the one-on-one pass-rush drill. Charlton and Collins got into a shoving match. Backup center Joe Looney and defensive tackle Brian Price came to blows. Frederick and unheralded Antwaun Woods got into it after one snap in which Frederick could be heard saying, "I'll kick your ass," which got Woods to tag him in the helmet, kicking off what was the most energized tête-à-tête of camp.

"You go against the same guys every day, back and forth, and one rep you get a hand up in a face," Martin said. "It's just competitive people going at it and something may break out. We've had a great camp so far. The D-line and O-line are really pushing each other. It's been a tough camp against those guys, but that's what we need."

Cowboys head coach Jason Garrett wants the Cowboys' identity to come from the offensive and defensive lines. He felt it was that way when he played in the 1990s with the Cowboys. Despite having "The Triplets" in Michael Irvin, Troy Aikman and Emmitt Smith, the backbone of those teams were Nate Newton, Mark Tuinei, Erik Williams, Mark Stepnoski, Tony Tolbert, Russell Maryland, Charles Haley, Leon Lett and Tony Casillas.

"Everybody is watching the two guys who are involved in it. Obviously, it's a very physical part of the game. It's also a very technical part of the game," Garrett said. "So those guys are all working on something. For half of practice, they're working on their sets or their hands or their get-off -- whatever it is -- and now we're kind of going to put it on display, see where we are."

At night, Alexander goes through a checklist on every snap: How is the stance, the set, the read, the hands. Marinelli wants effort. He wants to see a burst off the line and the ability to stay low.

"That drill puts us in probably the hardest situation you can have as an offensive lineman," said Martin, who has made the Pro Bowl in each of his first four seasons. "I actually really like the drill because it doesn't get much harder than that -- one on one, no help, no other guys setting with you. It really gets you better in pass protection."

Lawrence offered his take.

"It's mano-a-mano. You ain't got your boy trying to shove me in the hip no more. It's just me and you, so I'm going to make you move your feet," Lawrence said.

The rest of the team is off doing 7-on-7 work during the pass-rush drill. Most of the attention from the fans in attendance is on the throws from the quarterbacks to the receivers. Before the next period begins, Garrett will call on three offensive linemen and three defensive linemen for individual pass-rush drills in front of the entire team.

When rookie Dorance Armstrong was credited with a win on Smith, Garrett called for them to battle again. Smith tossed the rookie around on the next two snaps in a best-two-out-of-three matchup.

"The best thing about it is there's nowhere to hide," Alexander said. "You're out in front of everybody and you either do it or you don't. Do you rise to that challenge or do you get nervous and crumble? So it's obvious that it's a game for the strong."