On June 23, 2001, then-Los Angeles Lakers center Shaquille O'Neal made a surprise appearance during 311's performance at the annual KROQ Weenie Roast. Onstage with the rockers from Nebraska, he performed an original song called "Psycho" that featured creative input from a couple of 311's members.

But the live collaboration was notable for more than just the sonic partnership between the rapping athlete and the other musicians. The icon who's also known as Shaq — he often used the sporty nickname in the titles of his hip-hop albums from the 1990s — ended up with a bloody mouth as he crowd surfed during what sounded like a new rap-rock direction for the 7-foot-1 entertainer.

Watch the footage down toward the bottom of this post.

"Psycho," at one point laid down in a studio version that featured 311 guitarist-vocalist Nick Hexum and drummer Chad Sexton along with Korn's Fieldy on bass, was earmarked for a 2001 Shaq album that never materialized. The effort, which had a provisional tracklist and many hip-hop collabs alongside the more agressive nu-metal jam, was reportedly called Shaquille O'Neal Presents His Superfriends, Vol. 1.

L. Cohen, WireImage

"'Psycho' is just the other side of me," O'Neal told MTV News at the time. "The side that I'm really not allowed to show. It's just how I get sometimes. I get stressed out, and I get pent up."

Hexum contemporaneously added of the song, "He wanted to make a rock track where he's just going off, ranting and raving as this character called Psycho. He's going off about all the pressures that are on him and how he just has to bust out sometimes."

Although the Superfriends album remains unreleased, a studio version of "Psycho" can be found online. From 1993 to 1998, O'Neal released the albums Shaq Diesel, Shaq Fu: Da Return, You Can't Stop the Reign and, finally, Respect, which contains a track called "Psycho Rap (Interlude)" that may have been an early inspiration for the 311 team-up.

The 2001 KROQ Weenie Roast, held at the now-shuttered Irvine Meadows Amphitheatre (then the Verizon Wireless Amphitheatre) in Irvine, Calif., also hosted performances from Jane's Addiction, blink-182, Stone Temple Pilots, Staind, Linkin Park, Papa Roach, Coldplay, The Cult, Disturbed and more. The Weenie Roast has taken place every year since 1993, with the exceptions of 2020 and 2021.

Shaquille O'Neal Performs With 311 at the 2001 KROQ Weenie Roast

KROQ's Kat Corbett and Stryker Remember 311 + Shaq Weenie Roast Performance

311's Nick Hexum Remembers Weenie Roast Performance With Shaq

Shaquille O'Neal, "Psycho"

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