Burgess Hill Town picked up a vital point as they drew 0-0 away at Potters Bar.
Haywards Heath Town also drew 0-0 in their Bostik South East game with Greenwich Borough to extend their unbeaten run to six games.
Heath's play-off rivals Horsham won 3-0 at Whistable while Hastings United lost 2-1 at East Grinstead.
In the SCFL Premier, Hassocks drew 1-1 with Little Common.
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