In a game pitting the biggest men against each other, how can one of football's smallest men in the trenches be one of its best?
"People have been asking me that since I've been in high school," said Rams defensive tackle Aaron Donald.
In the NFL, Donald outweighs only one starting defensive tackle -- the Cardinals' Frostee Rucker, a converted defensive end.
And Rucker is two inches taller than Donald, a two-time Pro Bowler who is listed at 6-1, 285 pounds.
Donald uses leverage and an explosive first step -- among other attributes -- to more than compensate.
While presenting him with the 101 Award for NFC Defensive Player of the Year for the 2015 season, CBS studio analyst and former Steelers head coach Bill Cowher called Donald "one of the most quick and disruptive players in the game."
At the 2014 NFL Combine, Donald posted the fastest 40-time (4.68 seconds) among defense tackles while benching 225 pounds 35 times.
Pro Football Focus gave Donald a 99.9 rating in 2015, breaking J.J. Watt's record for the highest single-season grade ever awarded to a player. Donald not only led interior players in quarterback pressures, but his run-stop percentage (10.9 percent) also ranked fifth in the NFL among defensive tackles.
His PFF mark made history, for which Donald has an appreciation.
He said he looks up to smaller three-technique tackles from years past like John Randle (6-1, 290 pounds), Warren Sapp (6-2, 303) and La'Roi Glover (6-2, 285).
But his coach, Rams defensive coordinator Gregg Williams -- a 25-year NFL coaching veteran -- won't compare Donald to anyone else.
"I refuse to compare him because I think he is in a world of his own," Williams said. "He's as good as anybody I've ever coached."
In addition to his aforementioned quick step, the diminutive -- at least by NFL behemoth standards -- Donald has the arm length (32 5/8 inches) of a much taller player. So he possesses the best of both worlds. Because of his short height, he can get his pad level under an offensive lineman to generate leverage and then use his long arms to easily separate from the blocker.
Before the snap, Donald -- through both film study and an innate sense -- also has an uncanny ability to read how his opponent is going to block him and where the ball is going to go, allowing him to attack accordingly.
"He can feel and do things in the game of football that only special people can do," Williams said. "He's one of the most fun guys I've ever had a chance to manipulate scheme (around) to let him maximize his instincts."
Williams employs one of the most complex schemes in the NFL, featuring 42 packages of defense. Though Donald is tough and durable, the Rams constantly use him on stunts so that the 285-pounder avoids the beatings caused by double-teams.
Donald is also aided by playing on one of the NFL's best defensive lines, which includes defensive end Robert Quinn (50 sacks in five seasons) and defensive tackle Michael Brockers (a first-round pick in 2012, the year after Quinn).
"They make my job easy," Donald said.
During his short career with the Rams, Donald has been labeled as a pure 4-3 tackle with B-gap responsibilities, but Donald could excel in any scheme. The Rams have some 3-4 looks, and during his sophomore year at Pitt, he was primarily used as a five-technique defensive end.
After receiving the Chuck Bednarik Award, Bronco Nagurski Award, the Outland Trophy and All-American honors at Pitt, he recorded nine sacks in 2014 en route to winning the AP's NFL Defensive Rookie of the Year.
"He snuck up on people his rookie year," Williams said. "Last year he snuck up on nobody. People game-planned for him every single week. He was frustrated early on in the season last year because he didn't start as fast as he thought he should."
But Donald, known for his work ethic, responded, recording 6.5 sacks during the second half of the season and now has posted an impressive 20 cumulative sacks in his only two seasons in the NFL.
Having adapted to offensive gameplans focused on stopping him, he faces another adjustment this year as his Rams are moving from St. Louis to play in Los Angeles this season.
"We're excited about it, a lot of opportunities out there for us," he said. "I know the fans are pumped up about it."
Like most of his teammates, though, Donald has not yet found a place to live in Southern California.
"We're all looking," Donald said.
Donald, who grew up in Pittsburgh, will soon get settled on the West Coast, but he is hardly content with his performance. Since the 2015 NFL season ended, he has broken down film of every one of his snaps from 2015.
"I ain't comfortable," Donald said. "I feel like I haven't played my best football yet."
-- Follow Jeff Fedotin on Twitter @JFedotin.
