Whitehaven 2010 head coach David Seeds criticised his side's effort after they were run close in Sunday's 14-12 home win against London Skolars.
Haven were pegged level at 6-6 at the break, and required winger Loz Hamzat's late try to seal the victory.
"We've got three points, we got a win, but I'm infuriated," Seeds told BBC Radio Cumbria.
"We disrespected London, they should have won. It was an unacceptable standard of rugby we played."
Haven were spared a bonus point defeat by a missed opportunity from Skolars wing Ade Adebisi, who failed to reach a loose ball close to the home sides' line with minutes remaining.
"We did our homework on London early doors, we set our stall out on Tuesday and talked about it," Seeds continued.
"I feel like I've spent my life telling them how to beat London and we've just disregarded it altogether.
"It was a poor performance, a lot of the lads feel sorry for themselves in there and so they should."
Seeds' side were docked 10 points under RFL rules for forming a new holding company but have won nine of their 12 Championship One league games.