"This is a kid we're talking about, so we have to take a wee step back," he said when asked about the decision to drop Sterling from the starting 11 in recent weeks.
"It is so mentally and physically draining, this league. It hurts experienced professionals and this boy has stepped up from the academy, played football and earned a contract off that.
"We have to nurture that and, at times, he has to have the mentality to keep learning.
"If he didn't kick another ball this season, he's had a good one, but what you are seeing now is more tiredness of the legs when before he could go up to people and take them on.
"That zip has gone and it's down to fatigue. Was that to be expected? Yes it was."
