Hernandez came on as a substitute in the 71st minute.
Everton FC is coming off a seventh-place finish in the EPL in 2010-11 and played this exhibition match without star goalkeeper Tim Howard. Jan Mucha got the start instead. The Toffees will conclude their exhibition tour at DC United on Saturday.
Both clubs struggled to find much offense in the first half with temperatures hovering in the low '90s. But when the clubs began to clear their benches after halftime, the offensive pace picked up.
Danny Mwanga nearly put the Union ahead in the 72nd minute but sent a shot just wide left from 10 yards.
Hernandez put Philadelphia ahead and then pumped his fists in celebration.
(Copyright 2011 Philadelphia Union. Reprinted by permission)