When you play a good team, they will have the ability to take an element or two of your offense away. V Tech did that in the 2nd half by doubling Rak, much like Nova did.
If the opposition has decent athletes and elects to double your big, you can't get him 21 shots. It would be great if life were that simple, but it isn't. When teams double Rak, Rak needs to find the open player, typically TRob, CMac, Kaleb or Silent G, and they have to make the defense pay by hitting the open shots they will get.
This is surely going to happen in almost every game the rest of the season and how the team reacts to it will largely determine how successful the season will be.