He told The Sentinel: "The speculation is tittle-tattle. Glenn did smashing for us last season.
"But he has been in a situation that a lot of Premier League players find themselves in.
"They get worn out. I don't just mean physically, but they get mentally drained too and they need to rest.
"Glenn always plays at 100 per cent, he never gives anything less, so it is important to recognise that the demands in the Premier League are different from those in the Championship. There will be times when players just have to rest."