UFC heavyweight Mark Hunt is back in the fold and about to return to the octagon with a fight against Alistair Overeem in Las Vegas on Sunday, but a burning sense of injustice remains.
He is a man on a mission to clean up the sport of MMA from what he says is the scourge of performance-enhancing drugs.
The New Zealand-born Hunt, who is based in Sydney, missed three fights after his defeat on points against Brock Lesnar in UFC 200 last year and at one stage doubted he would fight for the organisation again such was the disgust he felt after Lesnar tested positive for a testosterone booster.
Lesnar was Hunt's third opponent to test positive for drugs, and his anger remains strong. The American, a WWE star, announced his retirement from MMA a fortnight ago, and Hunt is pursuing legal action against him.
It means some of the joy has been taken from Hunt's return in UFC 209, a card headlined by a rematch between welterweights Tyrone Woodley and Stephen Thompson in the bright lights of the gambling mecca.