Diego Corrales and Jose Luis Castillo's epic clash is remembered by Adam Smith on 15th anniversary

Diego Corrales and Jose Luis Castillo produced "one of the greatest fights", writes Sky Sports Boxing's Adam Smith, on the 15th anniversary of their epic encounter.

This is a time when many have reflected on three decades of fabulous boxing memories on Sky.

Debate always rages about which was the greatest fight we have been privileged enough to show throughout our emphatic collection of modern classics.

Sky boxing's broadcasting pioneers Ian Darke, Glenn McCrory, Bob Mee, Gary Norman, Jim Watt and Paul Dempsey will all have their personal picks. In fact I know big Glenn will argue vehemently for the first extraordinary encounter between Erik Morales and Marco Antonio Barrera. Yes Glenn - that was right up there. Sensational!

Yet for me, as high octane and super skilled as stunning world championship fights and rivalries can be - there also needs to be a real twist in the plot. That sting in the tale as Roald Dahl used to call it. Most unexpected. Something utterly extraordinary. Something, quite simply, out of this world.

Well on May 7, 2005 what unfolded was just that, and exactly 15 years on I wanted to mark this anniversary of the most incredible fight we have ever commentated on for Sky Sports.

Jose Luis Castillo and Diego Corrales delivered it in bucket-loads.

The setting was the Golden Tower of Las Vegas's glistening Mandalay Bay - although Jim Watt and I were calling this from slightly less glamorous surroundings in the middle of the night - snuggled up together in VO booth 14 at Sky HQ!

We might have been cold and tired, but there was the warmest light as the sun was coming up when we left. For the pair of us had witnessed the most unreal of gladiatorial battles.

The fight was a grand unification in the prestigious old nine stone nine division, and this made it even more special for us because of course Jim had been a brilliant world lightweight ruler.

Born in Empalme but based in Mexicali, Jose Luis Castillo was a rugged world lightweight champion from a fighting family. His brother Roberto boxed and another Ricardo did pretty well at super-bantamweight.

Jose Luis gained much of his experience by boxing many many gym rounds with the amazing Julio Cesar Chavez, the wonderful three-weight king, and unfortunately that label of 'sparring' partner continued to stick with him for much of his career.

This wasn't fair. Castillo had a wonderful jab, superb left hooks to the body like so many of his countrymen, and these skills, mixed with a ferocious work rate made the rugged Mexican very difficult to beat.

Ask Floyd Mayweather - who arguably struggled with Castillo more than any of his opponents; some even felt Jose Luis should have inflicted the first defeat on Floyd's perfect slate back in April 2002. Mayweather of course won both of their clashes but it had been hard graft, and he was fairly glad to see the back of Castillo.

We had filmed plenty of tapes with Jose Luis high in the Mexican mountains, in a lonely, barren, spartan training camp - he was a very hard man.

Jose Luis Castillo entered that Vegas ring as WBC lightweight champion with a record of 52-6-1(46 KOs).

Diego Corrales had a career tally of 39-2(32 KOs).

'Chico' was a former super-featherweight king who lost his unbeaten record and title when he was taken apart by Mayweather - but who had rebuilt capturing the WBO nine stone nine belt the previous summer by stopping the amazing power-punching Brazilian Acelino 'Popo' Freitas.

Like with Jose Luis, we had spent much time with the fast-talking, charismatic Diego - who was adjusting to life under flamboyant Californian trainer Joe Goossen.

Tall, mobile, heavy-handed and skilled, we thought Corrales would have to box Castillo.

Goossen had other ideas, telling us: "People thought we were going to box, and we made them really think that, but I felt Castillo just applied too much pressure. That we would have to beat him at his own game early, break him down.

"Diego was actually a great inside fighter too, but we'd never really seen it. I'd noticed flashes so we decided to sit in the pocket. Nobody thought we were going to submarine the guy. Remember though, Diego never backed up in his whole life!"

Although it was a super match up, the timing saw it crammed into a packed fight calendar in 2005, and surprisingly it was really only seen as a good trade fight.

How wrong people were. What unfolded in Vegas that night was historic. Corrales indeed took the fight to Castillo. The Mexican then answered in equal measure. It was top drawer skills mixed with white-hot velocity and unimaginable commitment.

The two warriors literally stood toe to toe for nine rounds in a ring furnace. It was phone box stuff, but it wasn't crude. The punches were of extreme quality; this was classy but frighteningly brutal.

On they went. Ferocious combinations fired from one to the other, and back again with interest. After nine pulsating rounds, Jim and I were exhausted; who knows how the fighters must have been feeling! Literally baring their souls in the squared circle.

The 10th round was pure storybook.

Both of the throwback gladiators' eyes were swollen, pain etched on their faces, but the pair were so deeply committed the round just kicked off with more of the same.

Something you felt had to give, and it finally did.

A mighty left hook from Castillo - and Corrales was floored heavily. It looked like the end.

Yet up he rose.

Castillo looks out on his feet. Corrales - left, rights, Castillo's going to go here...

I can remember the commentary lines as though it was yesterday -

"Corrales is fighting on instinct. There's nothing left."

Then he was decked again. Heavier. Definitely curtains.

"Down for the second time in the round, can't see, wincing in pain, is this the end of an amazing affair?"

Corrales surely couldn't get up. Gumshield spat out. Trying everything to bide time. Point deducted by referee Tony Weeks. Castillo one punch away from the most amazing victory.

Corrales somehow - and really no one can know quite how - climbed back into battle but it looked certain no artillery was left to fire.

Wait. A Corrales right hand connects. Suddenly Castillo looks a little shaky - and then boom: "OH LEFT HOOK! Castillo looks out on his feet. Corrales - left, rights, Castillo's going to go here. It's been stopped - UN-BE - LIEVABLE.

"DIEGO CORRALES WINS ONE OF THE GREATEST FIGHTS IN THE LAST 10-20 YEARS!"

Jim and I were on our feet. Literally gobsmacked.

"If you'd seen it in a Rocky movie, you wouldn't have believed it!" Jim said.

Only twice when commentating do I remember standing up during the climax of a fight. The first was when Danny Williams dislocated his shoulder twice in a British championship meeting with Mark Potter. Fighting on nonsensically, in agony, his right arm virtually unusable, somehow Williams found a left uppercut to floor Potter and stop him.

Yet this was even better. World level. Non-stop action and an ending that just defied belief.

I walked out of that voice booth and thought about my 10, 20-year line. Maybe I had over-cooked it. That was a big call. It felt right at the time. As Diego was fighting on extinct, it just came to me. Spontaneously.

Of all the fights I had seen up to that point on Sky, it was the best, and of all the ones I have seen since 2005, it remains the stand-out clash.

Fortunately others quickly started raving about what they'd witnessed and the fight just gained more and more momentum in the days afterwards.

Joe Goossen told us: "Both were supremely talented, they had five-star technique. They also used every trick in the book. They absorbed a lot of punishment. It had everything. Those triple left hooks from Corrales. Body attacks from Castillo.

"Diego told me he was the hardest puncher he'd ever faced. They were two willing warriors steeped in old school mentality."

Ironically, we were in Vegas the week after for another promotion. I just couldn't stop thinking and talking about it. I called up Diego and I persuaded him to come to the MGM media room. I found him sitting in a corner by a coffee machine. His face showing all the scars of battle.

It was the only time I had ever heard Diego Corrales quiet. Ever.

There were few words. There was just the realisation of quite what he had to endure for that marquee victory. The best of his career.

Steve Albert for Showtime had said: "Diego Corrales said he would go through hell before losing this fight. He may have had to"…

This was to be Corrales' finest hour, and it had taken so much out of him. Diego's career - and life - would sadly never quite be the same.

Castillo came in three and a half pounds heavy for the rematch, Corrales took the risk and got knocked out in four.

We were there all week for the trilogy fight in June 2006 - 'The war to settle the score' - but there never was a war. Castillo had come in ludicrously over weight again - almost five pounds - and the fight was scrapped.

Tragically as you will read in my other feature this week, Diego died on his beloved motorbike two years to the day after winning this battle of the ages.

Jose Luis boxed on. In fact he had another 19 fights. Yet he could never scale those heights to world champion status again.

Corrales and Castillo. Their immense fighting hearts and their names etched in history together for a boxing night and real-life story that will be among the greatest there has ever been - and ever will…..