The NFL finally got its version of the home run chase -- a record run it could promote the entire season -- with the 2000 Rams. Little does it know, the league also has its Mark McGwire, or at least a thirtysomething slugger who's astounding everyone with his youthful play.

Trace Armstrong leads the league in sacks with 10. When you consider the Miami Dolphins defensive end is 35 and plays mostly in passing situations, his production can definitely be considered McGwire-like.

Armstrong is on pace for 26 sacks, which would eclipse the single-season mark of 22 set by Mark Gastineau of the Jets. The 12-year veteran is accomplishing all of this by playing only 52 percent of the defensive snaps in a Dolphins defensive line rotation that's aided Miami's 5-1 start under Dave Wannstedt.

"He's just a true competitor," Dolphins defensive end Rich Owens said of Armstrong.

"He's playing like a crazy animal," defensive end Kenny Mixon added.

He'll be the oldest sackmaster, too, if he can break Gastineau's 16-year-old record. Since the NFL started recording individual sacks in 1982, the oldest player to lead the league was Kevin Greene, who was 34 when he posted 14½ sacks for Carolina in 1996.

Armstrong is definitely old school, too. At 6-foot-4 and 270 pounds, he is hardly the prototypical size for the modern-day NFL pass rusher. He isn't even the Dolphins' fastest lineman (Jason Taylor and Owens are the team's renowned speed rushers).

However, Armstrong does know how to outwit the opposition in a team-oriented scheme that has allowed him to enjoy individual success.

"I think it is mostly the guys around me are playing so much better; particularly in passing situations," Armstrong explained. "Our inside guys are doing a tremendous job of getting push in the middle. When you are an outside edge rusher like me -- if a quarterback is able to drop back to six yards, seven yards and step up and throw from five -- it is very difficult to get sacks. But when you are getting push in the middle, he has got to stay back there in his drop and that just gives you more opportunities to get to him.

"Everybody is playing well. And when you have that, you create sack opportunities for each other."

Armstrong took advantage of an overwhelmed Buffalo offense in Miami's last game -- a 22-13 victory in Week 6 that saw him collect a career-high 3½ sacks and force two fumbles. He's only two sacks away from tying his career-best 12 in 1996.

The Dolphins aren't the only ones benefiting from Armstrong's onslaught. As a member of the "Crunch on Paralysis" team for the Cystic Fibrosis Foundation, Armstrong is making a donation for every sack and tackle this season.

"There are no words to describe how he's playing," Mixon said. "He's a great technician, and he's been around for a long time. He knows how to get to the quarterback."

Joe Lago is the NFL editor for ESPN.com.