The "X-factor" exists in the sports lexicon as one of those words universally understood, but not necessarily defined. To borrow a phrase from — and applied for a much different reason by — the late Associate Justice of the Supreme Court Potter Stewart, I know it when I see it. 

D’Angelo Amos is an X-factor for No. 2-ranked James Madison. The redshirt junior impacts two of the three phases of the game as both a safety and punt returner. 

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Coming off a 2018 season in which Amos garnered All-American recognition for his effort as a returner, his best play may still be yet to come. 

“I’ve really seen him elevate his play the last three, four, five weeks,” said Dukes coach Curt Cignetti. “He’s tackling [well]; he’s making plays in the pass game. He’s very dependable.”

That kind of player provides an X-factor: an ability to change the trajectory of a game at a moment’s notice. 

Using five moments from the 2019 season, Amos shows exactly why you’ll know an X-factor when you see one. 

Sack of Austin Kendall at West Virginia

James Madison’s stellar defense features some of the best sack-creators in the nation between linemen Ron’Dell Carter, John Daka, and Mike Greene. Blitzing opposing quarterbacks isn’t something Amos is called on to do much, but he opened his 2019 season with one at West Virginia. 

HIGHLIGHT | Amos brings down Kendall for his first sack of 2019!#GoDukes pic.twitter.com/5v8RTuib6C

— JMU Football (@JMUFootball) August 31, 2019

The way in which this play unfolds demonstrates Amos’ patience and discipline in coverage. As the pocket collapses around Mountaineers quarterback Austin Kendall, Amos spies. Kendall starts to make a move forward, at which point Amos recognizes the quarterback’s commitment to run and attacks accordingly. 

INT in Chatty

If an X-factor is agreed upon as a game-breaking play, look no further than Amos’ interception of Chattanooga quarterback Nick Tiano. 

The play of the game in @JMUFootball's win over Chattanooga Saturday was an interception by D'Angelo Amos in the 3rd quarter

JMU was up 23-14 but the Mocs were about to score

On the ensuing drive Ben DiNucci connected with Brandon Polk for a 48-yard TD, making it 30-14 pic.twitter.com/VX3bzBtxHY

— TJ Eck (@TJEck_TV) September 22, 2019

This is quintessential safety savvy, reading the quarterback’s eyes throughout his progressions. Amos then springs the trap, jumping the receiver’s route to snag the would-be scoring pass and flip the field in James Madison’s favor. 

Villanova Denied

Amos leads the nation with three blocked kicks on the season, a remarkable stat on its own. Against Villanova, his third block denied the Wildcats their first points of the game. That’s crucial in a contest where the Dukes trailed in the fourth quarter. 

HIGHLIGHT | D'Angelo Amos swats his third blocked kick of the season to stymie Villanova's opening drive and keep the JMU lead at 7-0!#GoDukes pic.twitter.com/k68LJ4jcxX

— JMU Football (@JMUFootball) October 12, 2019

On both defense and special teams, Amos is often the fastest player on the field. Speed is helpful in getting around the edge on a field-goal block, but here, he muscles his way through a would-be blocker. 

Punt Returns At William & Mary

An individual performance that garnered CAA Special Teams Player of the Week recognition included Amos’ season-long punt return of 49 yards. The run-back set the table for a Ben DiNucci touchdown pass. 

HIGHLIGHT | D'Angelo Amos takes the William and Mary punt 49 yards to set up the Brandon Polk touchdown! The return was Amos' longest of the season!#GoDukes pic.twitter.com/LkPmRMhoqr

— JMU Football (@JMUFootball) October 19, 2019

Upon swiveling past the initial would-be tackler after catching the punt, Amos is patient in reading the coverage. One second later, he turns on the jets and strategically runs behind M.J. Hampton. Amos’ mate in the secondary rewards his savvy return read with an outstanding block, turning what would have been a gain of maybe 10 yards into a 49-yarder. 

In total, Amos returned for 125 yards against the Tribe. Cignetti singled that out as a key to the conference win. 

“Those punt returns were a huge factor in the game early, creating field position,” Cignetti said. 

Touchdown-Saving Tackle At William & Mary

William & Mary struck first in the Week 8 interstate showdown, but Amos ensured it was only a field goal. Tribe offensive coordinator Brennan Marion came out with some innovative looks for the Dukes’ outstanding defense early, continuing coach Mike London’s recent pledge to get explosive freshman Bronson Yoder more touches. 

Out of the Wildcat formation, Yoder takes a snap and finds a hole. The speedster races through the second level and beyond the secondary. Few players anywhere in college football can match Yoder in a foot race – Amos happens to be one. 

His closing speed in pursuit of Yoder makes a difference between three points and seven in the early phases of the game. 

Amos denied William & Mary more points in this contest with a pass break-up in the end zone, as well as his second interception of the season. His chase of Yoder may have been the most impressive play, though, and the most impacting in terms of taking some wind out of the Tribe’s proverbial sail.