Tony Harrison accepted he only had a short training camp with his fighter, but the result was still an emphatic one as Teremoana employed patience before scything down Savage inside five minutes.

Much was said about the 28-year-old's need for a step-up in competition and during his first 10-rounder, he softened up an audacious American to head and body early before his fight-ending power showed itself.

Savage (11-2, 11 KOs) was biting on feints from the first few moments and had the wide-eyed look of a man regretful at what he'd signed up for, such was Teremoana's imposing presence and speed.

Andrew Moloney on commentary noted the 35-year-old's tendency to lean to his right and he hadn't landed anything in the opening frame, just circling before absorbing a leaping one-two combination in the final seconds.

"Everything will come together," said the 2024 Olympian's coach Gareth Williams between rounds and soon, the job was done.

An overhand right buckled Savage's legs, then he was countered with a straight right after advancing. Another two-punch combo left him wobbling, another shot sent him staggering to a knee and he stayed there, being counted out by referee Phil Austin.

Teremoana lamented the inability to get more rounds under his belt, but was nonetheless satisfied with a more measured display before hinting at returning on the Anthony Joshua-Tyson Fury undercard sometime in November.

"My first main event, I'm just very glad to have such an awesome man by my side in Eddie Hearn, who's going to take me all the way to the top. Everyone can see, I'm a lot more patient, the punches found their mark, I was hoping he was going to get up, that annoys me, but I'm looking forward to the challenges that come.

"What I've heard along the grapevine is I should be on the AJ-Fury undercard, the old heavyweights giving up their mantle so it'd be so good to get the new generation there, show them us Aussies have the thunder from down Under. It feels really good [to be on the undercard], great opportunity, this was just another step forward and this fight come November, another towards my goal of being world champion and then undisputed. What a blessing."

Matchroom chief Hearn echoed his sentiments, having been frustrated by domestic-level heavyweights rejecting offers to fight him previously.

"That's definitely the plan, we've got to step up the opposition and did that tonight, supposedly. Teremoana is too good, you see the fear on Savage's face, his eyes were popping out of his head and he didn't even land clean, we need to find someone who will get up.

"You've got to be a little bit patient, it's a build, we must face tougher opponents because he's got to do rounds but Australia has the best chance it ever has to have a heavyweight superstar, he can bring world heavyweight boxing here, the team are doing a great job, he punches so hard and as soon as he lands, the fight changes. If there's ever someone to crack the code in Australia and make it mainstream, it's this man."

Billed as the beginning of a career resurgence aged 34, former world middleweight title challenger Michael Zerafa (35-5, 22 KOs) began cautiously but finished with a flourish against Alejandro Ortiz.

Venezuela's heavy-handed Ortiz (26-1, 25 KOs) came out swinging with left hands in the opening round, Zerafa pawing at him with jabs and settling into a steady but unspectacular rhythm early.

Zerafa caught him with a right hand in the third, as he began chaining shots together. After being tagged by two left hands, he evaded capture and boxed off the back foot before landing a nice right hand set up by his double jab.

Ortiz walked forward intently in the fourth, applying pressure and found success with right hands late to finish a promising frame for the visitor.

This continued in round five, though Zerafa looked more composed behind the jab, pushing the 25-year-old back as he spent more time posturing in the sixth.

Both flattered to deceive shortly after Zerafa tagged Ortiz with a right hand in the seventh, they traded early in the eighth and the veteran was missing more theatrically when head-hunting. Just as you thought they'd go the distance, Zerafa hurt the Venezuelan.

Stung by a right hand and pinned up against the ropes, "Pretty Boy" unloaded with a barrage of unanswered punishment that had Ortiz in a bad way, slumped on the canvas. Despite surviving the final seconds, he was in no shape to continue and referee Paul Tapley waved off the contest after assessing him in the corner between rounds.