It was Mamaroneck's first league title since 2012.
"I think it's awesome," Mamaroneck coach Mike Chiapparelli told Daily Voice. "We haven't had one in like three years. That's the first step. Now we go for the sectional title. That's the hard one."
Mamaroneck's last sectional titles came in 2008 and 2009 - and both years the Tigers went on to win the state title.
Hayden Cohen tossed a one-hit shutout Thursday to beat the Knights. Andrew Gross doubled and drove in five runs for the Tigers, who upped their record to 14-4.
Victor Flack took the loss on the mound for Mt. Vernon, which fell to 4-13.
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