David Eckstein served as both a catalyst and finisher as the St Louis Cardinals moved within a win of capturing the World Series with a 5-4 victory over the sloppy Detroit Tigers.
Eckstein started a seventh-inning rally with a double and drove home the go-ahead run in the eighth with a two-base hit, helping the Cardinals to a commanding three games to one lead.
St Louis could win its first championship since 1982 with a victory in Game Five on Friday night.
It looked like the Tigers were on their way to evening the series after they built an early 3-0 lead.
But their defence deserted them, pushing them to the brink of elimination for the first time this postseason.
In the seventh inning, Tigers centre fielder Curtis Granderson slipped and fell on a routine fly ball, allowing Eckstein to reach second.
A throwing error by pitcher Fernando Rodney on So Taguchi's sacrifice attempt allowed the Cardinals to tie the game at 3-3.
Preston Wilson's single with two outs in the seventh gave the Cardinals a 4-3 lead.
After the Tigers tied the game in the eighth on Brandon Inge's double, defense again proved costly in the bottom half of the frame.
Yadier Molina led off the bottom of the eighth with a four-pitch walk off Joel Zumaya (0-1). Aaron Miles bounced into a forceout and moved into scoring position on wild pitch as Juan Encarnacion struck out.
Eckstein then followed with his fourth hit, lining a 3-1 fastball that tipped off the glove of diving left fielder Craig Monroe, scoring Miles with the go-ahead run.
Adam Wainwright (1-0) who gave up Inge's shot to the right-centre field gap, pitched a perfect ninth to send the crowd of 46,470 into a frenzy.
