Republic of Ireland international Murphy has emerged as a key member of Keane's side in recent weeks as Sunderland have put together a run of excellent home form to drag themselves out of the immediate fight for Premier League survival.
Indeed, they have won the last four on the trot with Murphy having started three of them, and scored as many goals, to cement his place in the team.
Keane said: "Daryl, particularly over the last four or five weeks, has been outstanding.
"I had a good chat with him. There was speculation he might be going here, there and everywhere. I had a chat and told him basically we are delighted with him and he is going nowhere.
"Players need that sometimes. Every player just sometimes needs a five-minute chat to say, 'Listen, we are delighted with you'. He's a good pro, he trains well, he looks like a footballer, he is a good athlete and he is doing well for us."
The manager added: "He's a good player. Every club we have played, nearly every manager I have spoken to has spoken very highly about him after the game, and that's always a good sign.
"He's a good player and a good lad, a very good lad."