Chris Stone’s men suffered a five-wicket defeat at leaders Bashley (Rydal) and have now gone five games without a win.
It is a massive fall for Havant having claimed back-to-back titles in 2016 and 2017.
The visitors made a strong start after their New Forest hosts put them into bat first.
Harry Gadd (96) and Stuart Ransley (62) shared an impressive 145-run first-wicket partnership.
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Apart from Richard Hindley (32 not out), however, the middle order failed to capitalise on the good start and the visitors finished on 261 for eight.
Despite Havant’s Freddie Gadd recording bowling figures of three for 54, Bashley were never really in trouble with the bat and reached their target with ease.
Burridge ended a three-game losing streak with a 66-run win at Lymington.
The visitors had to recover from a disastrous start that saw Sullivan White dismissed lbw to the first ball of the innings.
Joe Collings-Wells (45) and Hilio de Abreu (97) led the recovery helping Burridge to reach 243 all out.
Alec Damley Jones (five for 24) bagged spearheaded the visitors' bowling attack to leave Leamington's reply in tatters.
Meanwhile, in division one, all-rounder Fraser Hay again showed his quality as Portsmouth cruised to an eight-wicket win against Ventnor at St Helen’s.
The Aussie claimed five for 44 with the ball and scored an unbeaten half-century.
Joseph Kooner-Evans (three for 17) also impressed as Ventnor were bowled out for just 84 runs.
Josh Hill (67) continued his rich vein of form in Sarisbury Athletic's 89-run success against Rowledge.
Hill, who notched a century in last week’s National Village Cup quarter-final success against North Perrott, top scored as Sarisbury posted a target of 231.
Roulade were bowled out for 142, with Tom Kitcher three for 24.
In division three, both Fareham & Crofton and Portsmouth & Southsea picked up vital wins in their bid to avoid relegation.
Fareham & Crofton coasted to a 10-wicket win against basement-side Lymington II.
The visitors were bowled out for 121 with James Heniger claiming three for 19.
Heiniger (45 not out) and Dan Wimble (70 not out) guided the hosts home without any mishaps.
Portsmouth & Southsea ended a four-game losing streak with a 97-run victory against Fawley.