She's not like us!

Serena Williams had any tennis fans tuned into the Super Bowl doing a double take on Sunday night by making a special appearance in Kendrick Lamar's halftime show.

Williams and Lamar are both from Compton, Calif., and she made her appearance on stage during Lamar's performance of "Not Like Us," which recently won five Grammy Awards -- including Record of the Year and Song of the Year. 

Lamar centered his entire performance around the hit song, which is a diss track towards fellow rapper Drake that also features of a defense of Williams herself. In the lyrics of "Not Like Us," Lamar warns Drake -- whose legal name is Aubrey Graham -- to “not speak on Serena,” a direct reference to him having used the former World No. 1's name in the lyrics of multiple songs.

Posting on social media after the performance, Williams said she "died a little" in taking the stage.

The audience in New Orleans' Superdome and those watching at home reacted positively to Williams' appearance -- including Coco Gauff, who was watching live from Doha. 

"Loved the show and Serena ate that," Gauff wrote in a post on X, formerly Twitter -- also praising Samuel L. Jackson's appearance as the performance's guest narrator. SZA and DJ Mustard joined Jackson and Williams as celebrity guests. 

Gauff's fandom has precedent. When "Not Like Us" was released last May, Gauff joined Naomi Osaka on Lamar's team in the feud.

"I think pretty much everybody I know is leaning towards him," Gauff said at the time, saying that she appreciated Lamar's support of Williams. "I do like Drake as an artist, as well. But as far as like the rap battle that's going on, the rap beef, I think definitely Kendrick is winning."

But strutting her stuff with the world watching wasn't Williams' only Super Bowl LIX memory. Earlier in the day, she said it was "pretty dope" to be on the field before the Big Game -- and even sprinted from end zone to end zone in excitement.

Declaring "YOLO," or "you only live once," Williams decided to run the length of the field, saying: "When is the next time I'm going to be able to run on a field?"

Predicting that she could run the 100-plus yards in 60 seconds flat, Williams was cheered on by others in the Superdome after joking that she "could definitely not play football."