Georgie Groves has no illusion about the professional fight game.
It's either hit the other bloke with the equivalent of a sledgehammer - or expect the same back yourself.
The Hammersmith ABA champion is warming up for his pro debut at the O2 Arena on Saturday night as part of the undercard on manager David Haye's world title clash with Monte Barrett.
And Groves reckons that all that held sway in the amateur ranks, where he represented Great Britain more than 20 times, is worthless at his new level.
"You know those flicky jabs that score points in an amateur contest?" he said. "A decent pro can take those all day and not even blink.
"Unless you can hit with power you're nothing in the professional ring."
Since trading in his vest after retaining his ABA title in May, Groves has been training twice a day with Hayemaker Productions either at The Third Space swanky gym in Piccadilly, or as he did last week, at the Haye set-up in Cyprus.
There's nothing left to chance, with science ruling hope-and-hit and an emphasis on how much harder Groves can deliver knockout blows.
He said "There's none of that Rocky IV nonsense where punches are measured per so-many-pounds impact.
"But more an understanding of balance. Hitting hard isn't about hitting the weights and building up muscle. It's more about delivering with speed. And to do that, you've got to have balance."
The 20-year-old always reckoned he was made for pro fighting.
Needless to say, Haye and trainer Adam Booth reckon he's an even better prospect than former Dale Youth Club team-mate James Degale, who got the Olympic place - and eventual gold - that Groves had coveted.
The Hammersmith hammer admits he's relishing the thought of getting in front of a crowd at the former Millennium Dome, even though he still doesn't know who's facing him from the other corner.
He said: "It's not unusual - and I don't care who it is.
"If you worry about that, then you shouldn't get in the ring.
"It's at super-middleweight, and I know it's not Joe Calzaghe or Roy Jones Jr seeing as they fought last week - but one day it will be their equivalent."