The Bees go into Saturday's clash knowing victory will secure promotion to the Championship, while a draw or defeat would see Rovers go up and Brentford consigned to the play-offs.
"This is going to be the biggest game of my life and of some of the other players' lives," Dean told the club website.
"In my first full season this was exactly what I wished for. It couldn't have gone any better.
"It was nice to play Chelsea in the FA Cup and to play at Stamford Bridge but we knew that nothing was going to come from that.
"It was good for the club and a bit of profile for the players, but this game on Saturday gets us into the Championship which is where we want to be playing.
"So for the management, the players, the staff and the fans it's going to be the biggest game of our lives. I don't think there is a bigger game being played anywhere on Saturday than our game."