An early second-half goal by Broadbridge Heath's Dan Sandell sealed a hard-fought away victory.
He scored the only goal of the game when he netted from the six-yard box after a short cross from the right.
YMCA threatened the most in the first half as Sam Schaaf looked an imposing figure up front.
He first fired over the crossbar with an early chance and later shot low and hard but straight at Heath keeper Michael Chester.
Phil Johnson shot into the side-netting as the home side looked most likely to score before the break.
But it was Heath who were first out of the blocks at the start of the second half.
Sandell gave them the lead with his first goal for the club from close-range from a cross from the right just by Rob Godfrey as some fans were still making their way back from the clubhouse.
YM responded with a low headed chance by Nick Sullivan which was cleared by keeper Mark Fox.
The home side had another golden opportunity to equalise through Scott Buchanan who ended a lovely passing move by shooting narrowly over the crossbar,
YMCA: Fox, Curtis, Evans, Gilbert, Harding, Cooke (Shipton 51), Gedling, Johnson, Schaaf (Buchanan 74), Cave, Sullivan
Unused subs: Hunter, Gathern, Jeal
BROADBRIDGE HEATH: M.Chester, Godfrey, Robinson, S.Chester (Balfeur 77), Maxwell, Griffin, Sandell, Findlay, Holmes (Maher 75), Martin, Sultan (Copestake 85)
Unused sub: Clark
REFEREE: Rob King (Crawley)