Rockland fans were hoping for a closer game, but it was the Tigers who grabbed a 2-1 lead after one and never looked back, going up 4-1 after two en route to a 5-1 victory.
Team captain Will Kirk came up big - scoring a hat trick for Mamaroneck, which advances to a regional game Saturday vs. Section 10's champion.
It was Mamaroneck's first sectional title since 2009.
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