On September 28, 1938, with the game about to be called by darkness at Wrigley Field in Chicago, player/manager Gabby Hartnett launched a solo shot to left that was lost in the night as it sailed over the wall in left to beat the Pittsburgh Pirates 6-5. The game was crucial, as it knocked the Pirates out of first, and would place the Cubs atop the standings where they would remain until season's end. The Cubs ended up being swept in the World Series by the New York Yankees. However, the ride to winning that National League Pennant would forever be remembered, and Hartnett's home run that came in the dark would become an immortalized moment known as the "homer in the gloaming."
As the 37-year-old Hartnett circled the bases an eruption of more than 34,000 cheers filled the air. He was mobbed by his team, and the fans as well before the ushers on hand were able to get him away from the celebration. In an article that was published in the Spokesman Review on April 9, 1950, Hartnett looked back on the moment in great detail. He began by saying "Do you know how you feel when you're real scared, or something big is going to happen? Well, that's how I felt for one terrific minute on my best day in baseball." It is an absolutely great piece of work that you can read here: http://news.google.com/newspapers?id=vXpWAAAAIBAJ&sjid=oeUDAAAAIBAJ&pg=6740%2C4128911
You could also check out the SABR account of the game here: http://sabr.org/bioproj/topic/sep-28-1938-pittsburgh-5-chicago-cubs-6
Check out the box score here: http://www.baseball-reference.com/boxes/CHN/CHN193809280.shtml