The pundit feels the 'football advisor' will have designs on the manager's job at Derby.
Indeed, Gray feels Redknapp's experience will be vital for Derby but also doesn't believe him when he says he isn't interested in the manager's job.
He said on Channel Five's Football League highlights show: "He brings his experience. If he's going to be a part of this season, he has to be on the training ground. Upstairs, that's not that big of a change.
"If the results don't go well, it really wouldn't surprise me if he goes in the dugout. [Kelly Cates quotes Reknapp saying he'll leave if Wassall goes]... He's got to say the right things but he wants to be in that dugout, there's no question about that."
It'll be interesting to see how Redknapp gets on at Derby long term.
Either as coach or advisor, Redknapp is deeply out of touch with the game. His work as a pundit proved that. But, at Championship level, experience often seems to trump knowledge of the modern game.
Redknapp didn't have any problems in the Championship at Queens Park Rangers but did in the Premier League. And look at the job Neil Warnock is doing at Rotherham United.
In the top flight, the 67-year-old would be worryingly out of his depth. In the second tier, though, he is working his magic...