This is how the Post described it:
Harper had come to the plate in the 12th inning Tuesday night at Nationals Park, with two outs, the score tied and the bases loaded, a chance to end an impossibly wild game after more than four hours. Down to his last strike, Harper drilled a sinking line drive to left field that gave the Nationals a 7-6 victory over the New York Mets, completing his team’s third comeback of the night and making him the first teenager since 1988 to smack a walk-off hit.
It was an end to a truly amazing and incredibly weird and strange game. But WOW was it great!