STEVE McClaren believes Derby County are entering a crucial period of the season.
"For all the teams battling for promotion, January is a critical month," said the Rams' head coach.
"You come through December and breathe a huge sigh of relief because there are so many games in that month, and then you have to go again," added McClaren.
"It is a mentality thing."
Derby's unbeaten run of nine Championship matches ended when they lost 1-0 to Wigan Athletic on New Year's Day.
They return to league action tonight when they face leaders Leicester City at the King Power Stadium.
"December was very good for us, and November was almost perfect as well but the run had to come to an end, we know that," said McClaren.
"What I have asked for now is a reaction.
"We have been riding the wave. We have fallen off the surf board and we have to get back on it and ride another wave. Let's not wait a few weeks to do it, let's try and start it tonight.
"The players have gained belief from the run we went on.
"It doesn't matter that one or two results don't go your way, you may have a dip, everybody does. It is how you come out of that and how quickly you come out of it. How you get back to winning ways.
"This is why I am so interested to see the mentality of the team. Can we against the odds go there (to Leicester) and get a performance and a result, and play like we have been playing over recent months?
"Tonight will not make or break the season but it will give us a fair indication of what we have got in the dressing room, and that is what we will find out."
A win tonight would see Derby climb into the top two on goal difference and close the gap on Leicester to four points but McClaren does not see the Rams as title contenders.
"No, not at the moment," he said.
"I think there are teams stronger than us - Burnley, QPR, Leicester.
"Nottingham Forest have got a very strong squad, and they will come as well.
"For teams below that, watch out for Wigan. Leeds are always strong, Reading too.
"They are all in contention and we are all fighting for that play-off spot, I suppose.
"That is what we wanted when we arrived, to get into the play-off pack. We are in there."