Former super middleweight champion Callum Smith is expecting a tough outing when he returns on August 20th in Saudi Arabia - as part of the undercard to the heavyweight rematch between Oleksandr Usyk and Anthony Joshua.

Smith made his light heavyweight debut last September, as part of the undercard to the first Usyk vs. Joshua encounter.

He made a statement at 175 with a bang - when he scored a scary one-punch knockout of Lenin Castillo.

Castillo went down hard and was lying motionless in the ring, which frightened Smith and his handlers. 

However, Smith made his presence known at the weight class - now with new trainer Buddy McGirt.

"There were a lot of question marks surrounding me on certain things. How will I fare at the new weight? How will I be coming back from a loss? How will I be under Buddy [McGirt, his new trainer]? I felt I ticked them all," Smith said to Sky Sports.

"I knew it was potentially a tricky fight," he continued. "He'd never been stopped. But I felt really, really good at the weight, I felt really strong and landing early on it was having an effect on him and obviously landed a good shot which finished the fight."

Smith will next face tough challenger Mathieu Bauderlique in a world title eliminator.

"[People] kind of assume I've been given an easy touch in a final eliminator but he's a good fighter, he's European champion," Smith said.

"He went to the Rio Olympics. He got the other bronze [medal]. He's got good skills, he's got good amateur pedigree, he's got good boxing ability. A little bit heavy handed when he lets them go. It's a tough fight. It's got my respect, it's one I'm taking seriously.

"He can handle himself, he's a good fighter and it's a big opportunity for himself. It's probably his biggest fight and there's a lot at stake for him. If I'm at my best I can beat anyone in the world at this weight and that includes Bauderlique."