Muhammad Ali -- CHILLIN' WITH SNOOP ... At High School FB Game

Muhammad Ali and Snoop Dogg -- SAT TOGETHER -- at the freezing cold high school state championship game in Reno, Nevada this weekend ... as their superstar kin DOMINATED on the field.

As we first reported, Ali's grandson Biaggio Walsh and Snoop's son Cordell Broadus are teammates at Bishop Gorman High School ... and both scored TWO touchdowns each in their 70-28 victory over Reed.

And get this ... one of Walsh's TDs was a 91-YARD run!!!!!

He's only a sophomore and is expected to be one of top running backs in the state next year.

As for Snoop's son -- he's a senior and this weekend's game was his last as a high school player. He's been offered scholarships by some of the biggest college programs in the country ... but has yet to announce where he's going to go.

With the victory this weekend, Bishop Gorman finished the season as the #1 high school football team in the country.