That's what Ronda Rousey did earlier today (Fri., March 2, 2012) at the Strikeforce weigh-ins in Columbus, Ohio, as she headbutted her opponent, Women's Bantamweight Champion Miesha Tate, during their staredown.
It's not like it was unprovoked. Tate got right in Rousey's face and pressed her forehead up against her foe, likely in an attempt to signify her lack of intimidation at all the trash Ronda's been talking in the lead up to the fight.
The Olympian didn't take kindly to it, of course, and responded by shoving her head forward, leaving a bright red spot on Miesha's dome. She took to Twitter afterwards to say the following:
"Ronda thinks she's tough she tries WAY 2 hard, such a phony person & she'll probably get fined 4 trying 2headbutt me when I got in her face."
She quickly deleted the tweet, as noted by our friends at Bloody Elbow, but you can't stop the Internet, folks. Once it's out there, it's out there.
To see video of the two going head-to-head (literally) click here.