Accrington drop one place to second after losing to third placed Nelson by 3 wickets at Thorneyholme Road.
The three bowling points gained keep Accrington one point ahead of Nelson and two points behind new leaders Crompton with three games to play.
Professional Jurie Snyman hit an unbeaten 99 in Accrington's 207 all out with Khurram Nazir taking 4-56 and Hassan Fazal picking up 3-35 for Nelson.
Fazal removed Jonny Dack before a run had been scored and Sam Kelly had Graeme Sneddon caught by Sam Holt at 6, also without scoring.
Skipper Jacob Clarke (18) was trapped in front by Fazal at 31 but Snyman and Emile Haratbar (43) put on 67 for the 4th wicket.
The introduction of Nazir brought the wickets of Haratbar, Simon Hanson (2) and Sam Molloy (1) to leave Accrington 106-6.
Kian Farnworth (20) helped his professional add 73 for the 7th wicket before falling to a brilliant one handed catch by Neil Thompson off his own bowling.
Jon Hayhurst (7) also fell to Nazir at 190 with Thompson picking up Asad Khan (7) at 209.
Fazal returned to trap last man Oliver Lowe (0) in front to end the innings on 207 leaving Snyman stranded on 99, including eleven fours and two sixes, in his final innings of the season.
Solid knocks from Matt Pettinger (46), Thompson (42), professional Tyler McGladdery (29), Tom Bradshaw (19 not out) and Fazal (18) took Nelson to victory with nine balls to spare.
Kian Farnworth took 4-51 for Accrington, removing openers Fazal (18) and Sam Holt (13) at 46 and 49, McGladdery at 89 and Gul Sabir (5) at 166.
Pettinger and Thompson put on 72 for the 4th wicket before Thompson was run out at 161.
Hanson trapped Pettinger in front at 182 and had Russell Bradley (5) caught at slip by Clarke at 194.
Bradshaw kept a cool head to secure the win with Ben Dinning (9 not out) with him at the end.
The seconds were well beaten at Walsden.
Mohammed Tayyib took 2-36 and captain Antonio Lo-Giudice picked up 2-37 in Walsden's 239-7.
Harry Cunliffe top scored with 28 in the seconds 92 all out.
