After winning their opening 12 fixtures, their proud 100 per record was ended with a 19-run defeat against Southampton Travellers.
Home skipper Shiv Choudhury struck 81 as his side posted 227-7 after he had won the toss.
In reply, Bedhampton’s top order failed to lay good foundations. And though Zeeshan Hazell (56) and Syge Bologne (27) - batting at No 7 and 8 respectively - top scored, Mariners were bowled out for 208.
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Choudhury brought himself into the attack late on, dismissing both Hazell and Bologne on his way to 3-15 off three overs.
Bedhampton are 17 points ahead of Waterlooville 2nds while they remain 27 points in front of Ventnor 2nds with four weeks remaining. The top two go up.
Ville strengthened their promotion challenge helped by opener Tom Farley’s second league century of the campaign.
Farley’s maiden league ton had come in the first three weeks - 113 not out against Froxfield (he also scored 58 not out and 47 not out in his other innings during that period).
This time Farley batted throughout the 45 overs to end unbeaten on 108 as Ville posted 236-4 at Rowlands Avenue against Trojans 2nds.
Skipper Jake Charman (51) and Stan Reynolds (39) provided solid support.
Martin Shepherd (4-28) removed four of Trojans’ top six before opening bowler Tom Southall (3-32) was brought back for his second spell to take three wickets as Trojans were dismissed for 162.
Purbrook 2nds suffered a miserable trip to the Isle of Wight.
First, they were skittled for just 60. Then Aussie Sam Guerin blazed a rapid half-century as the hosts raced to a 10-wicket win in just 22 deliveries!
Chris Russell (3-16) and Dominic Brihmani (3-21) as Purbrook collapsed to 33-7 after winning the toss.
Three of the top four failed to score before No 8 Owen Davies (22) became the first - and only - batter in double figures. None of his colleagues scored more than five, and there were also 22 extras.
Guerin wasted no time once Ventnor replied with debutant F Lesley conceding 27 runs off just two overs and Nathan Snelling conceding 20 off his six balls.
Guerin is the leading runscorer in the division with 675 from 13 innings - and with a 184.62 strike rate!
Joseph Stretton’s unbeaten half-century carried Portsmouth 3rds to a seven-wicket win against Solent Rangers at Farlington.
Asked to chase just 115 for victory, Stretton compiled 52 not out as the target was reached in the 24th over.
Fahad Ahmad (3-30) had been Portsmouth’s leading wicket-taker, while no Solent batter scored more than 20.