The upstart promotional company announced Thursday that it has signed Ring and WBO junior welterweight champion Shakur Stevenson.

The long-rumored partnership officially brought The Ring’s No. 3-ranked fighter pound-for-pound and No. 1-ranked lightweight together with an ambitious company capable of paying eight-figure purses to boxing’s top talents.

“Line them up, one by one, and I’ll beat all the top guys once I get them in front of me,” said Stevenson. “With Zuffa Boxing, I’m going to go after the biggest fights in the sport and I will become the number one pound-for-pound fighter in the world.”

Stevenson (25-0, 11 KOs) has won world titles at 126, 130, 135 and 140 pounds.

Stevenson, 29, is coming off arguably his most impressive performance, a dominant unanimous decision over Teofimo Lopez on January 31 to win The Ring and WBO 140-pound championships and secure a world title in a fourth weight class. The slick southpaw from Newark, New Jersey, jumped four spots on The Ring’s pound-for-pound list after defeating Lopez, a two-division champion.

"Shakur is one of the best pound-for-pound fighters in the world," said UFC president and Zuffa Boxing co-founder Dana White in a press release.

"He's 29 years old, undefeated and already a four-division world champion. This is a massive signing for Zuffa Boxing, and I'm looking forward to promoting this next fight."

Signing Stevenson could set up a potential fight with Devin Haney, who is also rumored to be inking a deal with Zuffa Boxing. The two traded words on social media and even agreed to a fight at a catch weight of 144 pounds in early June. Haney (33-0, 15 KOs, 1 NC), The Ring’s No. 8-ranked fighter pound-for-pound, is a three-division world champion and currently holds the WBO welterweight title.

Former 140-pound titleholder Jose Valenzuela, who is signed with Zuffa Boxing, called for a fight with Stevenson after his second-round knockout of Edwin De Los Santos in their rematch on June 28 in Las Vegas. De Los Santos gave Stevenson one of his tougher fights, though the latter won a forgettable unanimous decision to win the then-vacant WBC lightweight title in November 2023.

Stevenson is the second current world champion to join Zuffa Boxing’s roster. Ring cruiserweight champ Jai Opetaia held the IBF cruiserweight title when the unbeaten Australian signed in January, but he was later stripped of that belt.

Stevenson entered the pro ranks in 2017 after winning a silver medal at the 2016 Summer Olympics in Rio de Janeiro. Two years later, he won his first world title when he beat Joet Gonzalez by unanimous decision for the then-vacant WBO featherweight title.

He immediately moved up to 130 pounds and won the WBO title thanks to a dominant 10th-round stoppage of Jamel Herring in October 2021. Stevenson went straight into a unification clash with WBC titleholder Oscar Valdez in April 2022 and outpointed him to become the unified champion and earn the biggest win of his career to that point.

Stevenson lost his belts on the scale nearly five months later, when he missed weight ahead of his unanimous decision victory over Robson Conceicao. He stopped Shuichiro Yoshino in his first fight at lightweight before beating De Los Santos to become a three-division world champion.

Stevenson defended the WBC lightweight title three times. His last defense of that belt was an entertaining unanimous-decision victory over William Zepeda on “The Ring III” card almost a year ago at Louis Armstrong Stadium in Queens, New York.

Stevenson was stripped of that WBC belt after his win over Lopez because he refused to pay a six-figure sanctioning fee for a fight that was not contested in the lightweight division.