I think you will certainly some some glycogen in the muscles for those matches. I think Steve has mentioned using the anabolic diet during rugby but was typically carbed up for the games. Carb depletion can lead to a rebound increase in glycogen storage. This is likely what was in action.
I have been eating ~ Zone parameters of carbs but taking those in post workout and only after a glycogen depleting workout. If I am just doing some ring work on a given day I'm pretty much meats and veggies. This has been going well but I am doing nothing as demanding as 80 min of rugby.
Bottom line IMO is you need adequate glycogen on game (possibly practice?) day to optimize performance.
"Survival will be neither to the strongest of the species, nor to the most intelligent, but to those most adaptable to change."