Tries from Alex Eckley and Gavin Rodden powered North Wales Crusaders to a 13-6 win away to Swinton Lions in a battle of the Betfred League 1's previously unbeaten top two.
North Wales leapfrogged Swinton at the top of the standings after a hard-fought contest in which Eckley's 30th minute try, converted by Tom Johnson, provided the only points of the first half.
Swinton pulled level eight minutes into the second half when Jack Hansen fed Rhodri Lloyd to dive over the line before Dan Abram converted, but parity lasted only 11 minutes.
Jordan Gibson's grubber down the line was collected by Rodden to cross, and Johnson once again converted. Brad Billsborough added a late drop goal to crown the day for the visitors.
The expansion derby in Birmingham went the way of the Midland Hurricanes, who enjoyed a 50-28 victory over winless London Skolars.
The Hurricanes raced into an early 12-0 lead with tries from Benn Hardcastle and Hayden Freeman inside the opening 10 minutes, but were pegged back by former player Harry Kaufman and Jarred Bassett either side of David Foggin-Johnston's try to level the scores at 16-16.
Elliott Windley restored the hosts' lead on the stroke of half-time and they made sure of the win after the break with further tries from Matt Welham (2), Freeman, Hardcastle, and Windley, while Bassett's second was consolation for London.
Lewis Sheridan and Gregg McNally both scored a pair of tries as Rochdale Hornets ran out 34-18 victors in their derby clash with Oldham, while Bradley Ho, Charlie Graham, Jack Miller and Mo Agoro scored the tries as Keighley Cougars won 20-16 at Hunslet, with Harvey Hallas and Wayne Reittie replying.
Centre centre Robbie Storey scored two of Doncaster's nine tries as they eased to a 52-16 win oer Cornwall.
Betfred League One Round 4 Results:
Rochdale Hornets 34-18 Oldham
Hunslet 16-20 Keighley Cougars
Doncaster 52-16 Cornwall
Midlands Hurricanes 50-28 London Skolars
Swinton Lions 6-13 North Wales Crusaders
