NFL running back Antonio Williams partners with Xfinity Series driver Joe Graf Jr.

Welcome to NASCAR, Antonio Williams.

The NFL running back released a video on Twitter late Thursday night that shares his backstory and reasons for partnering with Joe Graf Jr., driver of the No. 07 SS Green Light Racing Chevrolet in the NASCAR Xfinity Series. Their relationship began before the 2021 season began in February, as Williams became an official investor in Graf’s racing career.

The 2-minute video closed with: “YEAR OF THE UNDERDOGS. TO BE CONTINUED.” Friday afternoon, Williams and Graf announced Z Grills will sponsor Graf for several races this season, beginning at Phoenix Raceway on March 13.

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Watch Williams’ full video below.

A product of the University of North Carolina in Chapel Hill, Williams joined the Buffalo Bills in 2020. He was released on Aug. 5 — the day after his grandfather died, he shares in the video.

“Two uppercuts back to back,” Williams said. “Twenty-two years old, chasing a dream. But man, I was hurting. All I wanted to do was be around my family at that point.”

As he drove from New York to North Carolina, Williams thought about his grandfather’s legacy.

“His love for NASCAR, me growing up with him watching it continued to flash over and over in my head,” Williams said. “With the platform I have from the NFL, I knew I had a shot of getting something done I probably couldn’t have done before. I wanted to continue his push and love for NASCAR by finding a way to join the sport, and that led to this connection with Joe. That’s what started all this — the continuation of my grandfather’s legacy, the start of a great friendship and partnership and the growth of hunger to get back in Buffalo and get on the field.”

The Bills have since re-signed Williams.

Graf is two races into his second full-time season. He finished 11th in the opener at Daytona International Speedway, then 20th on the Daytona Road Course. He has one career win the ARCA Menards Series from 2018 at Berlin Raceway in Michigan.

The NASCAR Xfinity Series’ next event is Saturday at Homestead-Miami Speedway — the Contender Boats 250 at 4:30 p.m. ET on FS1, MRN and SiriusXM NASCAR Radio. Graf will fire off from the 16th starting position.

Williams isn’t the first non-NASCAR public figure to recently join the sport. NBA legend Michael Jordan and Grammy-winning superstar Armando Perez — a.k.a. Pitbull — are both team co-owners in the NASCAR Cup Series. NFL running back Alvin Kamara has sponsored an entry in the NASCAR Xfinity Series, as well. They’re all new for 2021.