Leeds crashed to a 4-0 defeat to the npower League Two side, which Grayson conceded was a real blow to his side's preparations for life in the npower Championship next season.
Grayson said: "Everyone was disappointed on Tuesday We were flat in terms of our energy levels at Bury. It could be to do with the training we've been doing. We could have scored a couple of goals, but we know what we've got to work on.
"Hopefully it's just something that happened on the night. Hartlepool is now the next game after a disappointment.
"The players have always reacted in the right way and you would like to think they will be ready for the game and will be sharper and have a good work-out."
Source: PA
Source: PA