Hendon came out on top of this battle of the bottom two of the Ryman League Premier Division and put four points between them and their Essex rivals. It was not only a vital victory but it avenged one of the Greens' darkest days of the season when Grays scored four without reply.
There were a multitude of changes to the Hendon line-up, as well as positional alterations, with new signings James Harper - from Metropolitan Police - and Geo Craig, albeit as a sub, making their debuts. Going the other way, Karl Oliyide had left (he joined Enfield Town).
The Blues had shown that improved form when they beat Bognor Regis Town a week earlier and they took this confidence into the game. In the first few minutes, Kieron Bishop and Joao Carlos - both of whom had enjoyed success against the Greens in previous matches - looked dangerous, but Luke Tingey and Arthur Lee answered all the questions they posed.
Hendon were certainly bolstered by the return of confident Tom Lovelock in goal and his vocal support helped Jamie Smith and Sam Murphy - the latter forced to fill in at left-back - out wide. In front of the back four, Laste Dombaxe was a willing runner, while Harper and Matt Ball brought a calmness and creativity to the midfield maelstrom.
With so much at stake, it is not surprising that the game was rather cagey. Hendon, however, also offered potency in attack Marcel Barrington's power complementing the craft of Kezie Ibe at the spearhead and Reis Stanislaus doing the creative work just behind them.
Dombaxe was narrowly wide with one effort and had another saved by Amadou Tangara. When Grays had opportunities Barney Williams forced a save from Lovelock, while Jon Ashton put a header over the crossbar.
Hendon made the key breakthrough just before half-time and it was, by this time, a deserved lead. It was Stanislaus who broke the deadlock, taking advance of an errant pass and a defensive slip to run through on goal and fire past Tangara.
Ball's influence grew as the game progressed and Grays struggled to copy with the quality of his runs and passes but an early second-half shot didnâ€™t trouble Tangara. It wasnâ€™t all one-way traffic and Bishop saw a deflected gathered gratefully by Lovelock.
The Blues' urgency rather affected their accuracy and a number of good openings were wasted by bad passes, inaccurate shooting or taking the wrong options of passing or shooting. Carlos set up Lartey Sartong with a clever pass, but he scuffed his shot at Lovelock, who saved easily.
Grays were also very quick to make changes, Harry Watkins, Lheureux Menga and Etienne Kaboola replacing Kabena Osei, Matt Baxter and Carlos, all before the midway point in the half. Kaboola had a great chance to level matters, but his effort flew high over the bar.
Tangara was the busier of the two goalkeepers and he made a good punching save of a dangerous ball from Murphy, and the produced an altogether better save to keep out a drive from Stanislaus.
The decisive moment of the match came with a dozen minutes to go. Tangara made a good save from a shot on the edge of the penalty area, but when the rebound fell to Ball, he was able to control the ball, steady himself and fire into the net.
Having got a two-goal lead, the Greens were content to run out time, and made their three changes. Elliott Charles replacing Stanislaus, Andre Da Costa coming on for Ibe and Keagan Cole taking over from Dombaxe.
But Hendon just don't seem to do things the easy way and, with five minutes to go, they failed to deal with a Grays raid and Sarpong put the ball in the net.
As the game moved into stoppage, there was an unpleasant incident involving Menga. He appeared to be bundled over, but his reaction was to stamp on the Hendon player. Tempers got heated and, when the referee had calmed things down, Menga was shown a straight red card.
It was just as well that there were only a few seconds left, because frustration levels were running very high.