It was Colback's first start under manager Paolo Di Canio and the midfielder-turned-defender admitted it had been tough to find himself out of the team.
He said: "Obviously it's disappointing. When a new manager comes in, there's always a chance that you might fall out [of favour] if he's got different ideas.
"But as a player, you've just got to keep your head. I have come off the bench each time and then played today. You have just got to keep focused because you can be thrown in at any moment, and you have got to be ready."