He was one of my favorite Twins during those years and some day I'll dig out my "Berenguer Boogie" poster from my parent's house that highlighted a sort of "Super Bowl Shuffle" dance in honor of Juan.
Here are a few cards from my Pancho Villa collection:
Without a doubt the worst prospect cards have to be these from the 1979 Topps set. It looks like they've taken the original photo and photocopied it about three times.
1979 Topps #721 Juan Berenguer
Are rare "Juan smiling" card.
1984 Topps #174 Juan Berenguer
His first Twins card:
1987 Topps Traded #5T Juan Berenguer