Siddal suffered a second National Conference League defeat of the season in agonising fashion away to Pilkingon Recs on Saturday.
The Premier Division leaders lost 33-28, having fought back from 25-0 down to get their noses in front entering the closing stages.
The Chevinedge men, fresh from thumping home wins over top of the table rivals Wath Brow and Leigh Miners Rangers, were not at the races in the early stages at Ruskin Park.
Recs, who had lost 78-0 to Halifax’s professionals in the Challenge Cup in March, stormed ahead with four converted tries and a drop goal from stand off Gregory Smith, their star man.
Siddal got into their stride, with number six Shaun Garrod again to the fore, and after pulling back 10 points before the break continued in the ascendancy.
Tries from backs Elliot Hodgson, Billy Hammond, Benjamin West and Garrod, plus one from second row Tom Garrett and four goals from Gareth Blackburn gave the visitors a 28-25 advantage.
However, their St Helens hosts snatched the spoils with a converted try and a penalty.
Siddal remain two points clear of Leigh Miners, who lost 16-10 at Wath Brow. Siddal host Lock Lane on Saturday.
Elland remain bottom of Division One after a 48-28 defeat by Ince Rose Bridge at Greetland.
The Calderdale side host fellow strugglers Millom next weekend.