The visitors took control in the early stages using their kicking game to turn the Scarborough back three and scored a couple of well-taken tries in the opening 10 minutes.
The visitors had the upper hand at scrum time but the Valkyries held their own when it was their put-in; they did struggle to get out of their own half but on a rare excursion into opposition' territory on the half-hour, full-back Mel Halstead slotted a penalty to reduce the arrears at 10-3.
Misfortune struck the local girls when fly-half Danielle Rowley was injured and was unable to be moved.
Both sides consulted with referee Alessandro Zavatti and the game was moved to an adjacent pitch where it continued; half-time was reached without further incident or score.
The Valkyries pressed for an equalising try during an attritional second half and spent extended periods in the visitors 22.
It looked as if the visitors may be tiring in the final quarter, but they defended with real commitment and following a series of scrums in the Scarborough 22, scored a try on the stroke of full-time for a deserved 15-3 win.
To a woman the Valkyries worked their socks off in what was a bruising encounter.
Unfortunately Rowley was taken to Scarborough Hospital and was treated for a broken leg.