"Once again it was really frustrating. I thought we started the game really positively and played some decent rugby early on, but every time we worked our way into the game, we made errors that shouldn't be made at this level of rugby," Diskin told BBC Sport.
"That's the sort of stuff you see by kids on a Sunday morning. We're making those errors week in, week out, which shows that these guys are a bit mentally fatigued, which is understandable."
Bradford continue their Super League campaign next Sunday when they travel to Warrington Wolves.