Rub the beef joint generously with olive oil followed by seasoning and garlic. Brown on all sides in a dry frying pan. Place in the slow cooker and pour over the Marsala wine. Add the carrots, celery, onion and fresh herbs.
Cook on low for 8 to 9 hours. Turn in the slow cooker every 2 hours and add a little more Marsala wine if the cooker begins to dry out. Allow to rest for 5 minutes before serving and slicing.