FOXBORO, MA - SEPTEMBER 27: Rob Gronkowski #87 of the New England Patriots looks on during the game against the Jacksonville Jaguars at Gillette Stadium on September 27, 2015 in Foxboro, Massachusetts. (Photo by Maddie Meyer/Getty Images)

These two tight ends are elite, but one is simply a different species, says NFL defender

Both guys have been doing this a long time, but one simply isn't on the other's level.

As the New England Patriots and Dallas Cowboys head toward a weekend tilt, Jason Witten and Rob Gronkowski will face off in a matchup of elite tight ends.

And while the duo has a similar skill set, at least one NFL defender thinks it's supremely difficult comparing Witten to Gronkowksi:

"Gronk obviously, he's Gronk," edge rusher Rob Ninkovich said, via WEEI. "He's a different species [with] his length and the things he's able to do. That's what makes him so special.

"[They're] two great great tight ends that have different characteristics in terms of build and the things they're able to do."

Witten is no slouch, but it's truly hard to compare anyone that has the rare athleticism, build and strength that Gronkowski does.

Tom Brady and the Patriots will face off against Brandon Weeden and the Cowboys at 4:25 ET from Dallas Sunday afternoon.