The Mavericks made the Chargers pay for the penalties. Leitner scored a 4-on-3 power-play goal with 5:18 remaining in the game to make it 3-1, and 66 seconds later, Grant scored a 5-on-3 goal to make it a comfortable three-goal cushion.
Minnesota State has swept three straight series, outscoring their opponents 24-9 in those games and 27-11 in the seven-game streak.
The Mavericks will return to Mankato today and will play the U.S. Junior National Team in an exhibition game on Tuesday at the Verizon Wireless Center.
Stepan is on the U.S. roster.
Minnesota State’s next regular-season game is Jan. 3 at Alaska.