Taylor Johns added 16 points and 12 rebounds for Riverside (10-10, 1-3 Big West), which snapped a five-game skid.
Jerron Wilbut made two 3-pointers as Northridge (6-12, 1-3) scored eight in a row to pull within one with 4:42 to play.
A layup by Johns made it 66-63, but Tre Hale-Edmerson and Wilbut each made a 3 during a 6-1 run that gave the Matadors a 70-68 advantage with two minutes remaining.
Larsson made a layup, Johns hit two free throws and Bland hit 1 of 2 foul shots to make it 73-72 with 24 seconds to go.
Smith led the Matador with 17 points.