Bob Arum hopes to see a more aggressive Efe Ajagba on Saturday night than the Nigerian heavyweight’s promoter has watched since Arum’s company signed Ajagba three years ago.

A lack of aggression has stunted the hard-hitting Ajagba’s growth, according to Arum, whose Top Rank Inc. has matched Ajagba against unbeaten Kazakh knockout artist Zhan Kossobutskiy on the Jared Anderson-Andrii Rudenko undercard. The 10-round battle between Ajagba (17-1, 13 KOs) and Kossobutskiy (19-0, 18 KOs) will open ESPN’s two-bout broadcast from Hard Rock Hotel & Casino Tulsa in Tulsa, Oklahoma, starting at 10:30 p.m. EDT.

“I think it’s a really good fight,” Arum told “We have the Kazakh fighter under contract with us. I don’t know who’s gonna win that fight. But it’s a real test for Efe and I wouldn’t be surprised if the Kazakh guy won.”

Passivity particularly impacted Ajagba’s performance in his last fight, a 10-round, unanimous-decision victory over previously unbeaten Stephan Shaw (18-2, 13 KOs, 1 NC). St. Louis’ Shaw was reluctant to engage, too, which made for a rather mundane main event on ESPN seven months ago.

The 6-foot-6, 235-pound Ajagba won that bout by the same score, 96-94, on the cards of judges Eric Marlinski, John McKaie and Don Trella on January 14 at Turning Stone Resort Casino in Verona, New York. That marked Ajagba’s second straight win since he suffered his lone loss – a 10-round unanimous decision to unbeaten Cuban contender Frank Sanchez in October 2021 at T-Mobile Arena in Las Vegas – but Arum wants to see more from the 2016 Olympian.

“I just think that he’s too passive in there,” Arum said. “You know, he’s gotta be more aggressive. I think everybody who watches him thinks he’s gotta take some chances. So far he’s been a safety-first heavyweight, even as big as he is and as strong as he is.”

Handicappers have made the unbeaten Kossobutskiy a slight favorite to beat the 29-year-old Ajagba. Kossobutskiy, 34, has won 12 straight bouts by knockout, yet this is the highest-profile fight of the 6-foot-3, 240-pound southpaw’s professional career.

Kossobutskiy was supposed to face Anderson (15-0, 14 KOs) in an ESPN main event July 1 at Huntington Center in Anderson’s hometown of Toledo, Ohio. A visa issue caused Kossobutskiy to withdraw from that bout.

Former IBF champion Charles Martin replaced Kossobutskiy on 11 days’ notice and gave Anderson the most difficult fight of his four-year pro career. Anderson dropped Martin (29-4-1, 26 KOs) in the third round, withstood some trouble in the fifth round and late in the 10th round and beat Martin by big margins on all three scorecards (99-90, 99-90, 99-91).

Keith Idec is a senior writer/columnist for He can be reached on Twitter @Idecboxing.