As NFL defensive players continue to adjust on the fly to what is and what isn't a penalty, J.J. Watt on Friday called a hefty fine levied against his younger brother by the league "insanity."

ESPN reported Steelers linebacker T.J. Watt was fined $20,054 for hitting Falcons quarterback Matt Ryan "in the knee area or below" during Sunday's 41-17 Pittsburgh rout.

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The elder Watt reacted with a pair of incredulous tweets, one quoting the ESPN report and the other a video of the play in question. "That is insanity," read the first.

On the second-quarter play, T.J. Watt blew past Falcons right tackle Ryan Schraeder before reaching out for Ryan's legs while stumbling to the ground. The quarterback has just released the ball, and Watt appears to make slight contact with Ryan's right leg, with Ryan eventually falling.

Watt was penalized for roughing the passer on the play — a flag that raised eyebrows among some at the time.

Through the first five weeks of the season, defenders around the league — most notably Packers linebacker Clay Matthews — have repeatedly vented their frustration over penalties called for hits on quarterbacks that don't involve the head or neck area.