Mahopac had tied it at 11-11 when defenseman Max Littleton scored his second goal of the game with 1:06 remaining in regulation to tie it.
It was the Tigers' third sectional title in the last four years. Mamaroneck had never won a title before taking the championship in 2012.
Mahopac has won nine sectional title in its history - the most for a Section 1 team other than Yorktown. It was the Indians' 16th sectional title-game appearance.
Greenberg and Littleton were named game MVPs. Danny Foley had four goals for Mahopac. Charlie Harris scored three times for Mamaroneck.
Mamaroneck has a bye from the first round of the state tournament. It will be play the Section 2/Section 9 winner in a state quarterfinal game Saturday, May 30 at Lakeland High School.
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