A balanced, patient Onondaga lineup provided flawless defense behind Walsh, including a play where infielder Josh Savacool (Baldwinsville) threw out a San Benito runner at the plate trying to break up the shutout.
Not only that, but Savacool scored twice and earned an RBI, as Walsh, Jeff Teague (Cicero-North Syracuse) and Avery Brooks (Henninger) also drove in runs.
The tournament continues Friday, with Onondaga facing Mobile (Ala.) at 1 p.m. Off on Saturday, Onondaga is back on Sunday at 10 a.m. to face Dexter, from Missouri, and meets the home team from Covington County Monday at 7 p.m.
Columbia Basin, Fond du Lac (Wisc.), Gulf Coast (Ala.), McCourty (Texas) and Cape Cod (Mass.) make up the pool of the National Division.