For the Marinade: Place the boar into a bowl large enough to hold it, plus 3 cups liquid. Add the red wine and red wine vinegar, the garlic (chopped or crushed), the rosemary and some salt and pepper. Cover and refrigerate for at least 12 hours.
For the Sauce:
If using fresh tomatoes, blanche them in boiling water, and then immediately place in cold water. Remove the skins and seeds. Place them in a blender or food mill until puree.
Remove the boar from the marinade and cut into small pieces. In a large skillet, heat 2 tablespoons of olive oil and add the boar. Cook it over a medium heat for a few minutes until it renders liquid. Remove from heat and place the boar in a colander so that the liquid drips away.
Dice the onion, celery and garlic and pancetta into small pieces. In a large pot, saute the onion and celery in olive oil until translucent, then add the garlic and the pancetta and cook until lightly golden. Add the boar and stir for a minute or two, and then add the red wine. After a couple of minutes, add the tomato puree, tomato paste, and salt and pepper to taste. Reduce the heat to low and cook for 2 hours, stirring regularly, until thickened. (If too thick, add a bit of water or beef broth.)
Cook the pappardelle until al dente, drain it and add it to the boar sauce. Heat for a couple of minutes and serve immediately, sprinkled with Parmigiano.