Otter had started strongly, leading 3-0, then 6-2, before a run of four goals by Amy Olsen and two more from Hannah Pritchett gave Leeds a 7-6 advantage.
It didn't last long. Otter hit back to go 9-7 up in the last period, only for spirited Leeds to respond once again with a Candyce Schroeder goal and another two and a half minutes from the end by Olsen.
In a frantic finale, both sides had a player excluded and both called time-outs - before Ferrone settled the issue at the death.
Photo below (by Trevor Hyde): Otter's Peggy Etiebet battles with an almost-submerged Candyce Schroeder.
Manchester completed a perfect start to their league programme with a 17-7 win against Hucknall.