Harrison’s advisers could hardly have picked a more fearless, not to say colourful, first foe.

Middleton, 33, spent four years’ active duty as a reconnaissance scout in the US Army a job which involved going behind enemy lines deep into Iraq and has a piece of shrapnel lodged in the right side of his neck to prove it.

‘‘We were blowing up an arms dump and someone let the ammo off on too short a fuse,’’ Middleton said. ‘‘Getting hit in the head (in the boxing ring) doesn’t really hurt.’’

Now Middleton, who comes into the fight with a modest record of eight fights and nine losses from 18 bouts, juggles his ring career with a job as a private investigator after gaining a degree in criminology from Florida State University.

He will be paid a career-best £3,500 for taking on Harrison after getting the call at his Florida home two-and-a-half weeks ago. That call represented a remarkable twist in the fortunes of a man who in January was contemplating flying over the Atlantic to star in an unlicensed bill in Essex.

‘‘I’d heard they wanted a fighter to fight for some obscure title. No matter how wacky the title, if it’s a title and you’re a fighter, you want it,’’ Middleton said.

‘‘I said I’d fight until I found out it wasn’t licensed. The British Boxing Board told me if I fought unlicensed I couldn’t get a licence to box in Britain again, and that the Florida commission would honour that ban. So I told them no way.’’

Still, such is the hype surrounding Harrison these days that even a man with Middleton’s experience of life in the fast lane admitted to feeling slightly ‘‘overwhelmed’’ with the attention which greeted him at their first head-to-head press conference yesterday.

Middleton’s trainer and manager are yet to join him and he admits to finding it tough in the boxing gyms around Wembley as he waits for his friends and his big night.

But he seeks solace in the fact that Harrison will have even more pressure resting on his own broad shoulders as the Olympic gold medal winner starts his bid to fulfil the lofty expectations which he himself has generated.

Middleton admitted: ‘‘Audley has got to be under pressure. The whole country is looking at him and he is a household name. I aren’t even a household name in my own household.’’