DeMarco was a top contender and I think he held the world title at one point, but I don't believe Stefan ever fought him for the title.
(I'll have to double check my information with my Mom and Dad...)
Here's the DeMarco fight. There's no sound and is very short, probably a highlight reel. Stefan is in white and DeMarco black. I'm not sure which rounds are highlighted here:
The first spot shows DeMarco besting Redl with some hooks pounding Redl's belly.
Then there's a break showing what looks to be the timer or bell ringer.
The second spot shows Redl besting DeMarco, pushing forward and wrestling in reaching jabs and left hooks. The aggression gets pretty notable, when DeMarco, clutches Redl, and collapses to the canvas, bringing Redl down with him. Redl is up first, followed by a slower and more exhausted DeMarco.
Then there's a break with showing a ringside photographer.
The third spot continues with Redl doing a slightly dirty trick. Note how he holds DeMarco's left glove against his body with his right elbow. I remember my Dad telling me about this trick. Your opponent can't pull his hand free, to protect himself or hit you because his glove is too big. Usually you do this on the opposite side of your body from where the Ref is standing. From the Ref's point of view, your opponent is "holding" you! Immediately after this Redl lunges forward with a left jab and DeMarco finishes up with a barrage of body shots before the Ref breaks them up for the end of the fight.
I think if my Dad had 5 more rounds, he would have knocked out DeMarco.
