When it is the home team that is at bat (bottom of the ninth), then the game is over when the first runner touches home plate, so anything after that is irrelavant. It is a "sudden death" type of play.. no need to continue because the home team is now ahead by one run. EDIT: If the home team is ahead when it is the middle of the ninth, then they do not finish the ninth inning, it is the end of the game at the middle of the ninth.. OFFICIAL RULES OF THE MAJOR LEAGUE: 4.09 HOW A TEAM SCORES. (b) When the winning run is scored in the last half-inning of a regulation game, or in the last half of an extra inning, as the result of a base on balls, hit batter or any other play with the bases full which forces the runner on third to advance, the umpire shall not declare the game ended until the runner forced to advance from third has touched home base and the batter-runner has touched first base. 4.11 The score of a regulation game is the total number of runs scored by each team at the moment the game ends. (a) The game ends when the visiting team completes its half of the ninth inning if the home team is ahead. (b) The game ends when the ninth inning is completed, if the visiting team is ahead. (c) If the home team scores the winning run in its half of the ninth inning (or its half of an extra inning after a tie), the game ends immediately when the winning run is scored.

The batter must at least touch first base otherwise he would be called out for abandoning.

Tibear is correct. Score would remained tied and go into extra innings. Whether the game-winning hit is a home run, double, single or even a walk, all base runners that are in a forced play situation are required to touch their next base before any game winning run (GWR) can count. If they don't, the outfield team would simply take the next ball put in play by the home plate umpire and make an appeal throw to the given base to force out the runner. If runners were on 2nd and 3rd and no one at first at the time the homer/single/walk is achieved, only then would the game end once the runner from third crossed home plate. The same if there were less than two outs. But as long as there are two outs, then every runner in a forced play situation MUST touch their advancing base for the run to be counted. This includes the batter, who is always in a force out situation when heading towards first.

tibear is rite even if a walk off HR is hit if ALL runners including the batter do not touch every base on the way to home the runners who missed A base or abboned the bases(went to dug out or out of baseline)are called out if it results in the 3rd out then the game shall resume if you dont belive me or want to argue with an actual baseball official look up the mlb rules section 4.09 ;p