Sheffield Tigers, with the National Three North title already safely in the bag, suffered their first home league defeat of the season when Ilkley scraped a 28-27 win in the final match of the campaign at Dore Moor.
Tigers were left to salvage two bonus points – one for scoring four tries, the other for losing by less than eight points – and have ended the campaign with 109 points, 16 clear of runners-up Wirral, who were edged out 37-32 at Rossendale.
That win puts Rossendale up to sixth place ahead of Sheffield, who were beaten 27-19 on their visit to relegated Huddersfield YMCA.
Dinnington held their sixth place in North One East despite being beaten 38-7 on their visit to second bottom South Shields Westoe.
Barnsley finished their Yorkshire Two campaign with an eight-try, 53-5 home victory over tailenders Castleford.
Wath on Dearne slipped to a disappointing defeat in Yorkshire Two, losing to Old Grovians who sit four places below them in the table.
Jack Fereday and Barrie Warriner both scored a brace as Mosborough took a 32-29 home win over Ossett. Full back Dale Adey scored the other.
Steve Mason and Aaron Lonsdale scored the tries as Rotherham Clifton beat Hessle 21-7.
Fly half Corey Cox added a conversion and three penalties.
Stocksbridge lost 63-5 at Yorkshire Three champions Wetherby, Sheffield Medicals were beaten 22-24 at home against Ripon, and Sheffield Oaks went down 48-13 to Hemsworth.