First it was his butt. Now it's his pelvis.

After collecting a 15-yard flag and $12,154 fine in Week 1 for twerking after scoring a touchdown, Antonio Brown and his penchant for excessive celebration ran into trouble again on Sunday.

This time, a few post-touchdown pelvic thrusts earned him a flag.

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The wide receiver snagged a 38-yard touchdown pass to put his Pittsburgh Steelers up 22-0 against the Kansas City Chiefs on Sunday. Brown followed with this celebration.

Antonio Brown got flagged for this, but it was totally worth it https://t.co/edpZwbjByk pic.twitter.com/wTWQDOcHi3

— SB Nation NFL (@SBNationNFL) October 3, 2016

The NFL fines players for "sexually suggestive" celebrations, so Brown may be slapped with another one. Last season, the league fined Von Miller $11,567 for thrusting, so Brown could face something in that range, though it may differ because this is Brown's second offense.

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After his flag in Week 1, Brown said he would try and contain himself and referenced Key & Peele's "two-pump rule" sketch.

“Well, I got to be smart in regards to that,” Brown told The Dan Gottlieb Show. “I never want to put my team in a bad predicament. Maybe I’ll keep (the twerking) to a minimum of two pumps instead of three.”

What's particularly curious is the NFL posted this tweet on Sunday, congratulating Brown on his performance and essentially endorsing his dance moves.

Make that 4 touchdowns on the season.

BOOMIN, @AntonioBrown. #HereWeGo pic.twitter.com/o8ZdO9iel1

— NFL (@NFL) October 3, 2016

If he is fined, the whole thing will feel a bit hypocritical, reprimanding a player after hyping him up. The contradiction was apparent to many on Twitter.

The NFL wrote "Business is booming" because they fine Antonio Brown for his celebrations, then use his celebrations in marketing and tweets https://t.co/F5mGH4PtCG

— Rodger Sherman (@rodger_sherman) October 3, 2016

NFL: if Antonio Brown's dancing is good enough for you to feature in your commercials, don't flag him for doing it. #SundayNightFootball

— Wartime (@BradyCrytzer) October 3, 2016

But, after all, this is the NFL, where the league's relationship with its players is sketchy at best.