The New York Yankees outlasted the Oakland Athletics in 14 innings to stay a game ahead of the Baltimore Orioles in their torrid American League East race on Saturday.
An infield error that enabled Ichiro Suzuki to score gave the Yankees their seventh consecutive win, a 10-9 victory.
Baltimore stayed in the hunt with a 9-6 12th-inning triumph over the Boston Red Sox for their sixth win in a row and 16th consecutive extra innings victory.
At Washington, the Nationals' Gio Gonzalez became Major League Baseball's first 20-game winner of the season with a 10-4 victory over the Milwaukee Brewers.
Gonzalez (20-8) pitched seven innings, striking out five and walking one while giving up three hits and two runs.
The Nationals, with baseball's best record, already are assured of a playoff spot. They lead the Atlanta Braves by six games in the National League East.
Ryan Zimmerman and Ian Desmond each hit three-run homers in the fourth inning as Washington took a 9-0 lead.
Milwaukee, third in the NL's Central Division, had a six-game winning streak snapped.
At Chicago, the reigning World Series champion St Louis Cardinals remained in the running for a National League wild card playoff spot with a 5-4 victory over the Cubs on John Jay's 10th inning run-scoring double. (Reporting by Gene Cherry in Raleigh, North Carolina; Editing by Ian Ransom)