Grant McCann insists his Doncaster Rovers players need to stick to the gameplan or risk being caught by their play-off rivals.
Rovers put in a sloppy first half showing in the 2-0 defeat to Shrewsbury - a result which meant sixth-placed Doncaster missed the chance to extend their two-point buffer over seventh-placed Peterborough.
"We started the game very, very poorly and we just didn't get to grips with our plan," said McCann.
"I thought we were outstanding in the second half and that's the way we know we can play.
"The players can't just be willy-nilly and do what they want to do - they have to stick to the plan.
"The boys have to realise that every game now is going to be a fight.
"We'll take this on the chin and move on to Saturday.
"It's the first defeat in six and we're still in good form.
"We've got 13 games left and 13 opportunities left to get to where we want to be."
Meanwhile, McCann is hopeful that influential midfielder Herbie Kane will not be on the sidelines for too long.
Kane, on loan from Premier League giants Liverpool, sustained a groin injury in the build-up to Tuesday's game.
"He felt his groin in training on Monday," added McCann, whose team host Charlton at the Keepmoat Stadium on Saturday.
"We'll see where he is over the next couple of days.
"We don't think he's too bad so we have to manage him and try and get him back as soon as we can."