The title had already been secured, but thoughts of a celebratory romp went out the window against a Tigers side who have fought to avoid relegation, and gave Ionians a good run for their money.
Winger Greg Mellor scored for the hosts after eight minutes and stand-off Mark Ireland converted. The visitors hit back with centre Lewis Minikin touching down after 14 minutes and kicking both the conversion and a penalty on the half hour to put his side 10-7 ahead at half-time.
Tigers retook the lead with left winger Henri Packard touching down just before the hour mark and Ireland converting, and that lead held until the 73rd minute when replacement Ben Bell crashed over and Minikin kicked the conversion.
Wharfedale climbed up to eighth place in the table after a 29-0 win over Peterborough Lions. Matt Houghton crashed over and full-back Rian Hamilton latched on to a grubber kick to add another.
George Hedgley secured their third try, and Joe Altham ensured the bonus point with a try.
Jack Blakeney-Edwards converted that score and he repeated the feat following a 70th-minute try from scrum-half Will Lawn.
Huddersfield battled back from a 22-0 deficit at Sedgley Park, but could not secure the win and ended up losing 22-17.
Guy Borrowdale opened their account, Chris Johnson converting, and Richard Piper added another. Johnson kicked the conversion and last-minute drop goal to secure a losing bonus point.
At Cross Green, stand-off Ben Smith’s 14th-minute penalty was Otley’s only score as they lost out 14-3 to Fylde.
Rotherham Titans’ first season back in National One ended with a 31-12 defeat at promoted Old Elthamians.
The hosts were 10-0 ahead before the Yorkshire side got off the mark with stand-off Callum Irvine touching down and scrum-half Alex Dolly converting. Elthamians extended their lead to 31-7 with three more tries before Rotherham’s next score, which came from Alex Nagle-Taylor, Irvine missing the conversion.
Scarborough’s hopes of promotion into the North Premier league were dashed for this season as they lost out 17-7 at Blackburn in their play-off match.
Yorkshire One runners-up Heath also missed out on going up, losing narrowly 24-23 to Durham/Northumberland One outfit West Hartlepool.
Twickenham-bound Thornensians lost out to Yorkshire Three rivals Baildon 19-17, while in the Yorkshire Four Shield knockout final Burley were narrow 26-25 winners over Thirsk.