Former NFL star Justin Blackmon has plead guilty to 1 count of misdemeanor DUI ... stemming from a December arrest in Oklahoma where video showed he could barely stand up straight.
As we previously reported, the ex-Jacksonville Jaguars wide receiver was pulled over around 3 AM on December 19th ... and claimed he only had 2 drinks before getting behind the wheel of his Jeep.
Cops weren't buying it ... and the dash cam video obtained by TMZ Sports shows the guy was absolutely hammered.