Otter led 8-3 at the halfway stage and looked in no danger. And it was still 13-8 to the London side at the start of the last quarter. But there was no stopping Sheffield after that - they levelled at 13-13 with a Kate Parkin goal two and half minutes from the end. Elizabeth Dunn scored for Otter but gallant Sheffield grabbed the points as Parkin scored her third goal with 44 seconds left and Victoria Ibbertson fired a long-distance winner - with seven seconds remaining on the clock.
Bernice Cowton and Laura Swift both scored four for Sheffield.