We just don't have the talent healthy to win without extreme defensive intensity, and because of the same injuries we don't have the depth to maintain that needed intensity. When we can do it for spurts we look good. In a game like purdue we were able to overcome the lulls with superior shooting, but that's just not feasible every game. Guys get wore out on d, don't get the breather they need, and the ball starts sticking on offense, tired legs getting no lift on jumpers, etc. The injuries just have a massive trickle down effect on every aspect of the game.
Just get experience and improvement for the freshman and Mav.