Sam Sexton has the 'look of victory in his eyes' ahead of his British heavyweight showdown – according to a fighter who has been close up and controversial with the man standing between the Norwich boxer and glory.

Paul Butlin has twice stepped into the ring against title holder Derek Chisora – and twice come away empty-handed after fights marred by controversy. Butlin claims he was head-butted in the first bout and then bitten by Chisora in the second – an incident witnessed by milions of fight fans on live TV, but missed by the referee, although it later cost the London fighter a fourth-month ban and a �2,500 fine. And while Butlin insists Sexton will be the next man to win the Lonsdale belt, he has warned him to beware of Chisora's unorthodox methods when they meet in Birmingham on September 18.

'He isn't the cleanest of boxers,' said Butlin, who went through a tough sparring session with Sexton last week. 'He chucks in his elbows, his head, he has bitten me – he even starts at the weigh-in as well, but he just seems to get away with it.Hopefully Sam can do his job and that will be Chisora finished. He's one of those people who lives off confidence and once his confidence is knocked he is the not the same man.

'Sam just needs to beware of everything, but with his jab and his boxing skills Chisora shouldn't get anywhere near him, that's the truth of the matter. I boxed Chisora second time with just five days' notice: Sam's had a proper camp, he's as fit as a fiddle, he's had great sparring, so I don't think Chisora will get past his jab.

'In that second fight Chisora was trying to beat lumps out of me and that's the reason he bit me, because he was frustrated. He does it to Sam and the referee will be on it straight away and he'll be thrown out.'

Butlin and Damian Campbell took alternate two-round shifts over 12 rounds with Sexton, and the Melton Mowbray-based man saw enough to persuade him to put a wager on Sexton winning. '100pc I'm on Sam,' said Butlin, who has just opened the Queensbury Gym in his home town.

'The sparring session was brilliant and Sam was as sharp as ever, but he's hitting harder.

'His fitness and his all-round boxing is as good as ever, and his thinking, and he just really wants this fight. You can see it in his eyes. It's all about the man who wants it most who wins it and I think it's Sam. I've boxed Chisora twice and I know he hasn't got much heart.'

n Tickets for the Sexton fight, part of Frank Warren's Magnificent Seven fight night at Birmingham's LG Arena, are priced at �40, �50, �80, �150 and �200 and are available from 07584 492345.