Speaking on the Stick to Football podcast from Sky Bet, Keane said: "I was harsh on Harry Maguire. You hope to keep it to footballing reasons and obviously, we cover a lot of Manchester United matches and he was struggling at the time.
"But you also think about the mental health of players and I definitely crossed the line with Maguire.
"I remember one time I kind of mocked him a little bit and that is definitely out or order. I crossed the line and listen, I played the game, I know it’s not easy.
"But I’m also big enough that I apologised to him. Sometimes we pundits get it wrong too."