On May 9, 1977, Ted Simmons capped off a nationally televised contest against the Reds with walk off home run against knuckleballer Dale Murray to give the Birds a 6-5 victory over the Cincinnati Reds at Busch. The odds were stacked against Simmons, as Murray had only given two home runs in 306 innings. However, Simmons guessed right on the trick pitch that he knocked out of the yard. The home run heroics were set up by a ninth inning that saw the heart of the Reds order come to the plate with the bases loaded and no outs before Al Hrabosky set the next three men down with three consecutive strikeouts. He worked around another jam in the tenth, before Simmons ended it with the big blast.
Check out the box score here: http://www.baseball-reference.com/boxes/SLN/SLN197705090.shtml