What we saw in Louisville was the end of Mike Tyson's career and the start of a fairytale for Danny Williams.
I think we might have seen the last of Tyson in a proper ring.
For Danny, a world title fight is definitely a realistic ambition now, and more importantly, he'll be able to put money in the bank - he deserves it after this victory.
It was one of those fights, and I have not been to many in 18 years of covering the sport, where I found myself standing on my feet cheering along with my colleagues.
Williams was given no hope by the American media and treated absolutely abysmally. Some of the newspapers refused to name him and called him "The Joker".
They had even shut down three or four blocks of downtown Louisville because they were expecting an enormous street party to celebrate a Tyson victory.
Admittedly, none of the British press thought he could win either, but we all thought he would come here and give a good account of himself, which he did.
So what happened was sensational. Having lost the first, second and the first part of the third rounds, Danny Williams turned the fight around.
By the start of the fourth round, we sensed victory and an incredible ending. Then Danny connected with a series of 26 unanswered punches.
As Tyson slid down the ropes the entire crowd stood in amazement.
With his head resting back against the second rope and blood trickling down his eye it was obvious he had no intention - and no way - of beating the count.
And that's when the bedlam erupted, 17,000 people gave Danny Williams the most rousing of receptions. The fans in the arena were not partisan - they were there for an event and that's what they got.
Danny will have made about £150,000 from that fight, which by the time he has paid his promoter 25% is not a great deal of money, especially when you have a six-week-old baby and a six-year-old daughter.
But, if he plays his cards right, he could now walk away with between £2-5m for his next fight.
And what now for Tyson?
He will possibly now go into something called K1 in Japan - a mixture of boxing and kick-boxing that generates serious money.
Most of the participants are not very good and even a shot Mike Tyson can become a star.
So don't rule out seeing him in Tokyo in the near future.
Steve Bunce was talking to BBC Radio Five Live.