The match, won 2-1 by the Black Cats, was at Derby 18 months ago and Keane said: "I didn't feel that strange. As a senior player at Manchester United and Celtic, I would have a chat with players. It was not as if I felt uncomfortable.
"I was always quite confident about talking to people, particularly about football.
"But I just remember speaking about Derby's goalkeeper in my team talk - before being told he had left the club. So that was a good start. I blame my scouts."