However, Johnson has said that Sterling merely responded to a question by saying that he felt some tightness in his thighs.
"Raheem was asked a question and he gave an honest answer," Johnson told the Mirror. "Now, it seems, he is getting punished for it. You learn very quickly in football that you can be too honest sometimes.
"Raheem didn't say he was tired, as has been claimed. He was asked a question about how he was feeling and he has said that his thighs were tight. There is a big difference between having aching muscles and actually saying to the manager 'I'm tired, I can't play.'
"Anyone with half a brain would know that's not the case. Raheem would play every week if he could. In hindsight, the whole thing could have been handled better. Instead, it has just added fuel to a situation."
Johnson has recently returned from a lengthy injury and could start his first game of the season when Liverpool travel to Queens Park Rangers tomorrow.