A Hull side ravaged by injuries none the less showed tremendous battling spirit and scored two late tries through Rob Nolan, but by this time Long had claimed St Helens' fifth score and with a 30-point lead the match was over.
Leeds Rhinos, meanwhile, will go into Saturday's Silk Cut Challenge Cup final in buoyant mood after rediscovering their form at the McAlpine Stadium where they hammered Huddersfield 42-20.
Returning to the scene of their semi-final victory over Bradford Bulls last month, Leeds produced an eight-try warning to their Cup final opponents, London Broncos, who travel round the North Circular to Wembley after a dispiriting run of four straight defeats.
Rhinos' second row forward Andy Hay and centre Marvin Golden made impressive returns from injury while Adrian Morley revealed his best form of the season. The full-back, Marcus St Hilaire, also returned, playing from the start and he joined Francis Cummins, Morley, Daryl Powell, Brad Godden, Leroy Rivett (twice) and Ryan Sheridan in scoring tries. Huddersfield's Jim Lenihan scored three tries and Matt Sturm grabbed one with the former Leeds scrum-half, Bobbie Goulding, kicking two goals.
Gateshead Thunder broke the 30-point barrier for the first time as they increased the pressure on the Salford Reds' coach, Andy Gregory, with a convincing 38-14 win. The victory, Gateshead's fourth in the last five games, took Shaun McRae's in-form side into seventh place in Super League.
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