"When he (Warnock) pulled me it was completely justified," Ifill told the South London Press.
"Most of the time when you're dropped you think it's the wrong decision and want to have a moan - but I couldn't argue.
"I scored against Watford and when you score it tends to gloss over it a little bit - because the people who weren't there think you must have done okay - but I knew I had been poor for three or four games on the trot.
"The gaffer knows me very well and just thought he would leave me out to work on a few things in training and get my confidence back."
Ifill has had a couple of weeks to prove in training that he deserves his place back.