This fight SHOULD have happened back in the day, and by most accounts, nearly did.
Under Pride rules, who wins and why/how?
Under UFC rules, who wins and why/how?
This has got to be in the top 3 ultimate fantasy match-up's (Chuck/Wandy, this, Fedor/Brock).
So who wins?
franks weakness was takedown defense
sak was good at defending subs
if sak wanted to, he'd win a dec with a few takedowns
This could still happen at Metamoris 
StevetheWeasel - Would have been an awesome fight.
I'd give Sak the edge, and keeping Frank on his back. But I can see Frank tagging him a lot, too. Who knows. Would have loved to see this.
I would agree with this.
Frank is too small for Saku
Frank by KO.
The closest Frank could get from PRIDE is for them to sign 'Sakuraba or like opponent' on the contract in their primes in 2000.
Say it happened in 99/00. What was Frank better at than Saku?
Does Anti-Jiu Jitsu work against Saku single legging him at will and putting Frank on his back. Frank had athletic subs, but Saku had better, and much more refined grappling. Frank had great cardio. Saku smoked a pack a day and fought for 90 minutes, so it's not like Frank was going to wear him out. Was Frank a better stand up striker? Nominally, at best.
I like Saku here, but both would have beaten Rickson.
Bobby Lupo - Say it happened in 99/00. What was Frank better at than Saku?
Does Anti-Jiu Jitsu work against Saku single legging him at will and putting Frank on his back. Frank had athletic subs, but Saku had better, and much more refined grappling. Frank had great cardio. Saku smoked a pack a day and fought for 90 minutes, so it's not like Frank was going to wear him out. Was Frank a better stand up striker? Nominally, at best.
I like Saku here, but both would have beaten Rickson.
Frank's striking was years ahead of Sak's.
Saku all day.
saku via armlock 
Sakuraba would've won. Too good on the ground, better wrestling by far.
Saku wins by kimura.
Sak would have easily won. How is this even a discussionÉ
Sakuraba`s list of opponents is a whose who of monsters. He was incredbile on the ground, unending cardio for days, and a person who took Igor Vovchanchyn the distance after fighting 90 minutes for fucks sakes.
He would take down Frank at will and either submit him or continue beating on him until he got a lopsided decision.
Just compare their careers, compare the level of opponents (Sak would literally fight anyone at any weight) and then look at Frank`s biggest weaknesses. Takedown defence and ground positioning (as evidenced by his fight with Jeremy Horn)
His greatest strengths were his cardio - which Sak had him matched in, and maybe he has the edge on the feet...but Frank was nowhere near the level of Igor V and I highly doubt Sak wouldn`t be able to nullify the game of possibly one of the most over-hyped fighters in UFC history.
Frank Shamrock vs. Kazushi Sakuraba is one of the best fights that never happened.
I think the idea that Sakuraba would have taken Frank down and out positioned him is probably spot on. Frank could hit, but its easy to forget that Sakuraba had a good, not great chin in his prime. I'd still love to see them in a straight grappling match.
WordUp -Bobby Lupo - Say it happened in 99/00. What was Frank better at than Saku?
Does Anti-Jiu Jitsu work against Saku single legging him at will and putting Frank on his back. Frank had athletic subs, but Saku had better, and much more refined grappling. Frank had great cardio. Saku smoked a pack a day and fought for 90 minutes, so it's not like Frank was going to wear him out. Was Frank a better stand up striker? Nominally, at best.
I like Saku here, but both would have beaten Rickson.
Frank's striking was years ahead of Sak's.
Marginally better.
Saku was trading with Prime Killer Wand and rocked him (before he got killed), Saku beat power stiker Rampage. Frank went life and death with Jeremy Horn.
Frank was the best under 200 LB fighter on the planet 1998-2000. In my opinion, he was the first truly cross trained fighter. The beginning of the next generation fighters, possessing explosive subs, def, stand up, great cardio and even incorporating yoga and movement techniques.
Dude was extremely tough, also.
I would go with Frank during that period.