Michael Floyd is now facing a mandatory 45 days in jail ... because his blood alcohol level has been revealed -- and it was VERY HIGH.
The Scottsdale PD says Floyd's BAC was .21 when he was arrested last week ... more than TWICE the legal limit of .08.
Because the BAC was so high, prosecutors hit the NFL star with 2 new serious charges:
-- Extreme DUI with a BAC of .15 to .19
-- Super Extreme DUI with a BAC over .2
Super Extreme DUI carries a mandatory 45 day jail sentence if convicted. The person must also install an interlock alcohol monitoring device in their car and may not drink alcohol for 90 days.
At the time of his arrest, Floyd told cops he had only had one or two glasses of red wine before he got behind the wheel of his SUV.
When cops found Floyd, he was passed out behind the wheel.