The Scots led 12-8 at the start of the final period only for Sheffield to come storming back, drawing level with goals by Bernice Cowton (2), Victoria Bowen and Danielle Elliot. However, Sheffield couldn't maintain that momentum into the final minutes as goals by Nicola Tate and Claire Moloney settled the match.
Champions Otter fell at the first hurdle - beaten 10-4 by City of Manchester. Stephanie Whittaker claimed four of the Manchester goals.
It was easy for Coventry, whose 22-6 defeat of Hucknall featured seven goals by Kimberly Watson. Liverpool Lizards also had no difficulty in accounting for Leeds Sharks - 19-7. Top goal scorer in this match was Katie Hesketh (Photo: Trevor Hyde), with six. They followed up with a 25-8 defeat of Hucknall.