Perham hit 47.4% (27-57) of their field goal attempts and placed three players in double figures. They led 29-24 but pulled away in the second half, outscoring the Grovers 41-21 over the final 18 minutes of play.
Leaders for Perham were Charlie Rasmussen (22 points, 7 rebounds, 4 assists), Finn Diggins (16 points, 5 rebounds, 3 assists) and Elijah Morris (15 points, 2 assists). Gunnar Anderson pulled down 7 rebounds for the Yellowjackets.
Oak Grove was led by Mason Martinson and Noah Swenson with 10 points apiece.
Perham will play at Park Rapids on Monday, host St. Cloud Cathedral on Tuesday and entertain D-G-F on Thursday.