Grant McCann felt Rovers dipped from their usual standards in the defeat to Fleetwood Town in Sky Bet League One.
Paddy Madden scored either side of Ash Hunter's finish to secure the win for the Cod Army, in what was Rovers' first league defeat since November.
He said: "We beat ourselves really and gifted them three goals, we'd spoken about Madden before the game but didn't deal with him.
"We played into their hands by conceding an early goal and then they settled into their formation which made it difficult. We lost Shaun Cummings at half-time and had to move players around so that didn't help us when we were trying to get back into it."
McCann promised his side would learn the lessons to take into Saturday's trip to Gillingham.
He added: "We lacked a bit of aggression in key areas. You have to gamble and want to get on the end of things, we were hoping things would happen for us and it doesn't work like that.
"It was similar to the game at our place, we got into some good areas but were trying to be too precise with the play."
Rovers return to the Keepmoat Stadium to take on Rochdale on New Year's Day, tickets are available from tickets.clubdoncaster.co.uk.