Steelers quarterback Ben Roethlisberger was spotted going after a defender's knees in Sunday's win over the Browns.

Very unique fighting style here from Ben Roethlisberger pic.twitter.com/EK4NOoLg1U — Sports Illustrated (@SInow) September 10, 2017

That defender was Browns defensive lineman Emmanuel Ogbah, who was perplexed as to why Big Ben was diving for his ankles. Not only did Roethlisberger go after him, but he then latched on to Ogbah's foot and wouldn't let go until the referee pulled him off.

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Even though these acts were done in front of the ref, Roethlisberger went unpunished. The play was scrutinized by fans, and the Browns weren't happy about it. Monday morning, fellow Browns defensive lineman Danny Shelton voiced his thoughts on Twitter by criticizing the NFL.

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His "QBsLeague" hashtag is a fair point, because the league has a lot of rules in place to protect quarterbacks. Several years ago the "Brady rule" was put in place. It says: "A rushing defender is prohibited from forcibly hitting in the knee area or below a passer who has one or both feet on the ground, even if the initial contact is above the knee."

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So defenders can't go after a quarterback's knees, but somehow a QB can go low on a defensive lineman? Seems like a double standard.

“I was just mirroring him and all of a sudden he just started grabbing my ankle,” Ogbah said after the game. “He was trying to twist it or something.”

While Roethlisberger wasn't penalized during the game, there is a chance the league looks over the play and issues a fine to the Steelers quarterback later this week.