has Nikolay Valuev ever been knocked down?

No

 

Almost down vs Jean-Francois Bergeron

 

Paul Briggs put him down in sparring when he was based in Australia I have been told,

 

This guy almost had him out...

[YT]KaigdKiO8Xc[/YT]

 

Valuev suffered one official knockdown in his fight with Elistratov.

 

Ruiz had him down but it wasnt ruled a KD.

 

There is no such thing as a standing 8 in the pro ranks.

 

Yes there is.

 

Sure there is, it just depends on what rules you're fighting under. No standing 8 count in the unified rules, but at least one state (can't remember which one) still has standing 8 counts.

 

No.

 

Liaaarrr!!!! Which one mother****er!?

 

I don't remember which one, but I remember seeing a fight not that long ago where someone was given a standing 8 count. It must have been a state without a commission though - the association of US boxing commissions banned it in the late 90s. Probably West Virginia, that's the commissionless state that has the most pro bouts. Hell, it might have even been foreign. But it still does exist, it's just not common.

 

Wladimir got an 8 count against Brewster in Vegas.

 

This.

Fight II.Round 2.