The champions' difficulties were compounded by fresh injury problems as the internationals, Martin Offiah and Kelvin Skerrett, joined the casualty list after leaving the field in the second half with hamstring and chest complaints respectively.
A try from the Hull substitute, Craig O'Donnell, after 68 minutes, converted by Paul Eastwood, proved decisive for the visitors but they were almost denied victory at the end as Joe Lydon failed to convert Steve Hampson's try.
A capacity crowd of over 9,000 at Thrum Hall witnessed another surprise as Halifax beat Leeds 26-8, the Yorkshire side running out of steam for the second week running. Leeds were unfortunate to have efforts from Shaun Wane and Ellery Hanley ruled out for forward passes but Halifax dominated a second half, highlighted by a superb try from John Bentley against his old club.
Sheffield Eagles secured their first win back in the top flight, thanks to two tries in three minutes midway through the second half. Sheffield, with the Australian, Garry Jack, making his debut at full back, scraped through 12-10.
St Helens continued their winning start, but were made to fight all the way for their 24-12 success over Wakefield. Six goals from Tea Ropati, and a third try from Alan Hunte three minutes from time sealed the victory for Saints.
Nottingham City celebrated their first win in 18 months. The Third Division team ended a 37- match losing run with a 19-12 victory at Barrow - their first triumph in any competition since beating Runcorn Highfield in March last year.Reuse content