Nate Diaz Stockton slap Maynard Keenan from Tool.

Brothers Nick and Nate Diaz have always been known for their infamous 'Stockton slap' amongst the hardcore MMA fan base, but younger brother Nate, 32, made the Stockton slap mainstream in his back-to-back fights against UFC star Conor McGregor.

Diaz, a former lightweight title challenger, taunted and slapped McGregor around the Octagon before locking up a rear-naked choke in the second round at UFC 196, handing the Irishman his first loss inside the Octagon. Diaz' Stockton slaps and epic post-fight interview ("I'm not surprised, mother fu**kers") earned him notoriety amongst the casual audience, and the fan favorite provided more theatrics in last year's welterweight rematch at UFC 202.

Diaz lost that fight via majority decision, but still entertained with his taunts and slaps.

On Thursday, Diaz hit lead Tool vocalist Maynard Keenan with the Stockton Slap and uploaded the video to social media.

Keenan, a Brazilian Jiu Jitsu purple belt, stopped by at Diaz' gym ahead of Tool's concert in Sacramento, California on June 23.

Diaz, a BJJ black belt under Cesar Gracie, hasn't fought since August of last year when he lost in the rematch to McGregor. The Ultimate Fighter 5 winner is currently being sued for over $1 million by a former agent.