Belal Aite-Ouakrim pounced for the only goal of the game in the 90th minute when home keeper Andy Walker failed to hold a stinging low cross by Dean Cracknell at Cray.
It was the sixth successive away game in which Hendon had scored in the 89th minute or later, and the third in a row where that late goal was a match-winner. They are up to 16th in the table.
Cray had much the better of the first half in a lively game but their pressure produced few clear chances and it was Hendon who came closest to scoring when a fierce drive by James Fisher was inadvertently blocked, almost on the line, by teammate Lee O'Leary.
The second half was more even: in the closing stages it was Hendon who looked more likely to break the deadlock. And, eventually, they did.
Our picture is an unusual shot of Hendon keeper Berkley Laurencin watching his colleagues clear their lines.
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