I needed to conquer what promised to be an especially tough bottom round roast from a steer who lived his life chomping only grass & clambering up & down mountainous terrain. The overnight marination along bringing roast up to room temp before grilling did the trick. We like our beef rare, especially for leftovers to be used in sandwiches & salads, hence internal temp of just barely to 140 degrees F. You need to check on your roast frequently after initial 30 -40 minutes to reach but not exceed internal temp you prefer (140 - rare, 160 - medium (barely pink inside)). Serve with Potato Gorgonzola Gratin & green salad with balsamic dressing & balsamic marinated onions. Yum, yum, yum. Try to choose a roast that has a shell or rind of fat on one side - it'll rest longest on that side on the grill & not dry out the meat. *Cooking time probably too long but does NOT include long marinade.