Roffey and Eastbourne both won to set up a potentially title-deciding match next Saturday between the two.
James Hockley, after his recent record-breaking 240, hit 139 as second-placed Eastbourne (301-7) beat Horsham (221 all out) by 80 runs..
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Scott Lenham (4-27) and Jacob Smith (3-32) were the pick of the bowlers.
League leaders Roffey (233 all out) beat Brighton and Hove (165 all out) by 69 runs. Rohit Jagota was top scorer with 89 while Simon Hetherton took 4-29 for the visitors. Jagota (3-13) and George Fleming (3-22) led the way with the ball for the home side.
Lewis Hatchett produced a stunning performance, taking 9-18, as East Grinstead (216-8) hammered Hastings and St Leonards (52 all out). Bradley Hatchett (44 not out) and Ian Sturmer (59) batted well in the lower order for EG before former Sussex left armer Hatchett below Hastings away.
Bottom club Ifield (55 all out) lost to Preston Nomads (230-9) with Navin Patel taking 4-9. Ifield and Hastings have now been relegated.
Cuckfield (208-8) beat Middleton (126 all out) with Tom Weston (71 and 3-23) putting in a fine all-round performance.
In Division 2, leaders Three Bridges (171 all out) beat Chichester Priory Park (130 all out) while second-placed Mayfield (243-6) triumphed against Billingshurst (117 all out). James Allen took 5-40 for Mayfield. A win for both teams next week will see them promoted.
St James’ Montefiore (211-6) continued their good form to jump into third place after beating Bognor Regis (192-9).
Tom Prideaux De Lacy (69) and Henry Sims (56 not out) starred with the bat for St James’ while Charlie Davies (5-18) was the pick of the bowlers.
Haywards Heath (238-5) beat Ansty (235-9), mainly thanks to Jonny Phelps’ 123 and Callum Smith’s 4-36.
Bottom-club Lindfield (131-4) gave themselves a slim chance of survival after beating fellow strugglers Bexhill (128 all out). Harry Chaudhary and Shohel Ahmed took three wickets each.
Division 3 West: Division 3 West: Findon 204-8 beat Worthing 197-9; Goring By Sea 93-6 beat Slinfold 91 all out; Steyning 80 all out lost to West Chiltington & Thakeham 126 all out; Stirlands 107 lost to Roffey 2nd XI (score tbc); Three Bridges 2nd XI 140-5 beat Pagham 138 all out. Highlights: GORING WIN TITLE.
Division 3 East: Brighton & Hove 2nd XI 64-2 beat Bexhill 2nd XI 61 all out (16.4); Eastbourne 2nd XI 70 all out lost to Burgess Hill 226-5; Hastings & St Leonards Priory 2nd XI 233-4 beat East Grinstead 2nd XI 229-7; Portslade 173-10 lost to Preston Nomads 2nd XI 197-7; Seaford 184-7 beat Crawley Eagles 179 all out. Highlights: Ian Simpson 103 not out and Dan Strange 7-28 for Burgess Hill; Greg Devlin 109 not out for Hastings.