Moses Itauma has vowed to return stronger after suffering the first defeat of his professional career against Filip Hrgovic in their IBF heavyweight world title fight at London’s O2 Arena on Saturday.

The 21-year-old was stretchered from the arena and taken to hospital as a precaution after the contest was stopped in the ninth round. Promoter Frank Warren said Itauma had “done something to his leg” and was “quite tired” following the bout, which marked the first time the British heavyweight had fought beyond six rounds.

“We attempted greatness and we just fell short to the more experienced man,” said Itauma in a video posted to Instagram on Sunday. “I want to say congratulations to Filip Hrgovic on his win and although I never reached my desired outcome, I believe I gained experience that I’ll take to my future fights.”

Hrgovic praised Itauma following his victory but said the 21-year-old’s relative lack of experience proved significant as the fight progressed. “He is the best fighter I have been in with but he needs more experience, he gassed out,” said Hrgovic post-fight. “I knew I had the pace in my favour. He gassed out but he is one of a kind.”

Warren said Itauma remains an exceptional prospect but believes changes will be required before his return to the ring. “He’s still one of the most unbelievable talents I’ve ever been involved with. We’ll stick with him,” said Warren. “He needs a bit more ring craft and needs to stop thinking about knocking everyone out.”

Itauma had never previously boxed beyond the sixth round and had not sparred for a full 12 rounds in preparation for the contest. Hrgovic backed his former opponent to eventually become a world champion but said he “needs more time”, while Itauma thanked supporters following the defeat and promised to return. “It was a f****** good fight and I want to thank Queensberry and DAZN for putting this show on,” said Itauma. “So God bless, take care and I’ll be back.”