Butland joined Rangers on a free transfer in the summer and has been one of the few new faces that have made an impact since joining the Glasgow giants.
He has been the undisputed number in the Rangers team this season and has been one of the constants of a team who have struggled for consistency in the ongoing campaign.
Grant worked with Butland when he was a coach at Birmingham City and admitted that his ability to be calm and provide confidence to the backline makes him a top goalkeeper.
He insisted that it was certain that Rangers were signing a top goalkeeper in the summer given the talent he saw in Butland earlier in his career.
Grant said on the Go Radio Football Show: “What I like about him as a goalkeeper is his calmness.
“He helps the backline; he doesn’t jump about. Makes a save, organises and gets on with it.
“He has been brilliant since he has come in.
“We always knew that if he was anything like when we worked with it, he would be a top signing.”
New Rangers boss Philippe Clement has also stuck with Butland as his number-one since arriving last month.
