The win brings the Redbirds within two games of the National League Central leading Pirates.
St. Louis (68-50) was given the opportunity to win the game thanks to an error in the bottom of the ninth. With one out, Daniel Descalso hit a routine pop fly to left, and Pittsburgh's Starling Marte let the ball bounce off the heel of his glove to the ground. Descalso -- on second after the error -- scored on Allen Craig's single three batters later to tie the game 3-3.
The Pirates struck first with an Andrew McCutcheon two-run home run off Adam Wainwright in the first, and a solo homer from Jordy Mercer in the second.
Wainwright went seven innings giving up three runs on five hits and three runs while striking out six.
Reliever Sam Freeman struck out one and walked one in the 14th inning, and picked up his first career win.
Jay finished the game going 4-6 at the plate with and RBI.
Matt Carpenter picked up three hits. Matt Holliday and Craig each had two.