Vagabonds lost narrowly at Liverpool Collegiate after leading for much of the game.
A Sam Brennan try, converted by Leigh Kennaugh, got them in front early on.
Kennaugh added a penalty to stretch the lead to 10-0 but Collegiate pulled back a penalty to leave the Vagas lead 10-3 at half-time.
In the second half, Collegiate bagged two further penalties and with just five minutes to go the game was balanced finely at 10-9.
Vagas switched off though in the closing stages and conceded a further penalty and a drop goal which cost them the game.
Rugby: IoM announces first national sides in over two decades
Football: Goals galore in Tuesday night clashes
NW200: Rain-hit qualifying gets 2026 event underway
Franco Bourne to make TT and Southern 100 debuts this year
Manx riders gearing up for 2026 North West 200