Launceston flanker and assistant coach Tom Rawlings said his side's 30-18 defeat by Taunton was a frustrating way to end their short winning run.
The Cornish All Blacks have been inconsistent all season, with home wins invariably followed by away defeats.
But back-to-back wins had raised hopes of a welcome change in fortunes.
"They wanted it a bit more which is frustrating because we've just had two good wins," he told BBC Radio Cornwall.
"We're disappointed to come back with nothing. We intended to make it three in a row but it's a very tough and competitive league.
"They took their chances and scored points at crucial times.
"We stuck at the task and kept fighting - it was nip-and-tuck and there was a crucial try awarded towards the end of the game which I think was questionable but we've got to go back to the drawing board.
"Credit to Taunton - they'd done their homework and we're going to have to look at our defence."
Launceston, who face Bournemouth at home next weekend, remain unbeaten at their Polson Bridge base.