I haven't read RC's link, but just in general; lunges, squats, leg press, explosive running
I'm no expert, and i'm not too technical with my work out, yet I know enough to say with some confidence that a balanced leg routine is the ****. Building your quads not only allows you to burn more fat (i think :/), but it tightens up ya knee, making it less susceptible to side hits and thus protects your lateral collateral and medial ligaments. Then of course it means better speed + leg drive.
With running, instead of a jog, for a short stint take a gentle pace, then for another short stint, break into a sprint. You've probably already done it mate, but if you haven't it simulates the explosive running you do in rugby and builds match fitness.
That's all I can add, like I said i'm no expert.