Goals by James Hadlow (2), Liam Humphreys (2), Sam Joyce and Adam Sperry left the Devon side stunned and put the Midlanders 10-8 ahead before Exeter finally responded with a goal half a minute from the end.
There were no heroics from Hucknall in their second game. They went down 14-10 to Southampton, whose scorers included Charles Roberts (5) and Christian Perress (3). Southampton also beat University of Bristol 9-4.
Birmingham and Watford were the only teams to retain 100 per cent records after day one. Birmingham beat York 10-5 and Otter 10-4. Watford led Otter until the third period when their London rivals briefly levelled at 8-8. Then last quarter goals by Gianluca Valle, Danny Davis and Nandor Cseh took Watford to an 11-8 win.