Bourne coaches John Forbes and Nigel Lindley were both seething with anger after seeing their side “push the self-destruct button” in the one must-not-lose game of the season.
Three yellow cards for Bradley Hiscocks, Harry Thornburn and Jason Goodyear left Forbes to attack his side for a lack of discipline.
Lindley said: “We pressed the self-destruct button and that’s from players who don’t train but just turn up and expect the results to come.
“Forget the local bragging rights, this was more about our league position and, after this defeat, the players have to decide what they want to do.
“They will play at the level they want to play at and this was like watching rugby on a village green.
“We’ve worked so hard this season on keeping the ball, but the core skills weren’t on show against Deepings.”
The one Bourne player to emerge with credit was Harley Giullari who kicked both penalties, despite being starved of service.
Giullari said: “We went into the game as forwards and backs with an aim to think strong and make tackles.
“I know we’re a good team, with strong players, but we need to stop dropping the ball.”
Skipper Tom Dixon said: “Our discipline let us down and we didn’t look like getting over the try line.”