"A squeeze or squeeze bunt is a bunt intended to score a runner from third base. A successful squeeze is scored as a sacrifice hit, unless the batter is safe at first without benefit of an error, in which case it can be a hit. The batter who executes a successful squeeze is awarded a run batted in."
Above posts are correct. It would be a single if no attempt was made at runner heading home and they still couldn't get batter out at first. There was a play like this in game two of the WCWS I believe.