Chicago Cubs celebrate David DeJesus's walk-off single in the 11th… (John Gress / Getty Images )
The St. Louis Cardinals' grip on the second National League wild-card spot weakened Friday with a 5-4 loss to the Chicago Cubs on David DeJesus' walk-off single in the 11th inning.
Before DeJesus' heroics at Wrigley Field, the fifth-place Cubs first needed a two-run, tying home run from second baseman Darwin Barney in the bottom of the ninth inning.
"I was worried about the wind, that the wind was going to knock it down, but it went," Barney said.
The Cubs' victory spoiled the season debut of Cardinals starter Chris Carpenter, who was coming off surgery related to a nerve ailment. Carpenter gave up two runs in five innings.
After St. Louis lost, the surging Milwaukee Brewers scored three times in the ninth inning to defeat the Washington Nationals, 4-2, and climb to within 1 1/2 games of St. Louis in the wild-card race.
Milwaukee's Ryan Braun and Aramis Ramirez had consecutive run-scoring hits in the ninth inning off the Nationals' Tyler Clippard to lead the Brewers' comeback win, their sixth consecutive victory and ninth in their last 10 games.
The Dodgers and Philadelphia Phillies also won to gain ground on the Cardinals in the wild-card race. The Dodgers are two games back, Philadelphia three.
Cincinnati and Washington, both division leaders, already have clinched playoff spots.
In the American League, Russell Martin's walk-off home run in the 10th inning lifted the New York Yankees to a 2-1 win over the Oakland Athletics, New York's sixth consecutive victory.
That kept the Yankees atop the AL East by one game over the Baltimore Orioles, who defeated the Boston Red Sox, 4-2.
"You can feel that playoff weather coming," said Martin, the former Dodgers catcher. "I like it. I enjoy it."
New York's CC Sabathia, who had lost his prior four starts, held the Athletics scoreless through eight innings and struck out 11.
Baltimore and Oakland also currently have the two AL wild-card spots.
The Angels cut Oakland's lead for the second wild-card spot to 31/2 games with a 6-2 win over the White Sox, as Chicago saw its AL Central lead over Detroit cut to 11/2 games.
The Tigers' game against the Minnesota Twins was rained out. They will play a doubleheader Sunday.
Times wire services contributed to this report.