The Grizzlies (19-1, 23-6 Big Sky) earned the top seed and hosting privileges for the conference tournament earlier on Saturday, when Sacramento State lost against Montana State.
Max Jacobsen led the Lumberjacks (8-12, 11-20) with 17 points, but only three after intermission. Northern Arizona earned the No. 7 seed in the conference tournament and plays No. 2 Weber State on Thursday.
Montana led 49-48 with six minutes remaining before a 12-1 run broke open the game.
The Grizzlies, who are 36-2 against Big Sky opponents the last two seasons, earned a bye to Friday's tournament semifinals and will play the highest remaining seed after Thursday's games.
ESPN's Dan Dakich joins The Paul Finebaum Show to discuss the SEC's presence in the NBA Draft.
Ted Kapita was the top-rated recruit from West Virginia in the class of 2015 and recently played at DME Academy in Florida.
With the Suns drafting Tyler Ulis, they now have five guards on their roster who attended Kentucky.