MOUNT Vernon — Jason Mustappa batted 4-for-4 with two doubles and three RBI to lead Mount Vernon to an upset victory over first-place Lake Stevens in a Wesco 4A North matchup. Senior Corey Bullens hit a two-run homer in the top of the seventh for the Vikings. At Mount Vernon H.S. Lake Stevens 020 000 2 — 4 6 2Mount Vernon 052 001 x — 8 7 2Cooper Nelson, Gaige Baisch (7), Ryan Frederickson (7) and Gabe Bueckman. Taylor Shea, Skyler Swords (5), Jeffery Sevey (6) and Matt Del Fante. WP—Nelson (1-2). LP—Shea (record). 2B—Jason Mustappa (MV) 2. HR—Corey Bullens (LS). Records—Mount Vernon 3-6 league, 5-8 overall. Lake Stevens 7-2, 9-4.