PITTSBURGH (AP) " Washington clinched its third National League East title in five years by winning 6-1 at Pittsburgh on Saturday, led by rookie relief pitcher Reynaldo Lopez, who threw 5-1/3 scoreless innings.
The Nationals were one of two teams to seal playoff berths on Saturday, along with Boston, which won at Tampa Bay to stretch its winning streak to ten games; the longest for the Red Sox since 1949.
The NL wildcard race is going down to the wire, with three teams competing for the two spots. San Francisco and the New York Mets are tied, half a game ahead of St. Louis, which defeated the league-leading Chicago Cubs.
In the American League, Toronto shut out the struggling New York Yankees to maintain a 1-1/2 game lead for the top wildcard berth, while Cleveland missed a chance to seal the AL Central title by losing to the Chicago White Sox.
Washington's Lopez was called out of the bullpen early, starting the fourth inning, and went through to the ninth without giving up a run. He struck out five and walked none.
The Nationals return to the postseason after a one-year absence. Their win ensured a playoff berth, and they sealed the division about 20 minutes later when the second-place Mets lost to Philadelphia.
Boston's Dustin Pedroia hit his fourth career grand slam to power the Red Sox to a 6-4 win at Tampa Bay.
Pedroia stopped an 0-for-17 slump at the plate with a single in the sixth and gave Boston a 6-3 lead with his four-run shot in the seventh.
Boston starter Rick Porcello claimed his majors-leading 22nd win of the season, giving up three runs and striking out nine over 6 1/3 innings.
The Red Sox maintained a 5-1/2 game lead over Toronto for the division title with seven to play and ensured they finish no worse than the AL's second wild card.
St. Louis got a boost in its pursuit of a wildcard berth by winning 10-4 at the Cubs.
Yadier Molina drove in four runs and Stephen Piscotty also homered for the Cardinals, while Randal Grichuk drove in three runs and Jhonny Peralta had three hits.
Toronto beat the Yankees 3-0 thanks to a three-run homer by Jose Bautista in the eighth inning.
New York has been shut out in three straight games for the first time 1975. The Yankees late surge toward the playoffs has faltered and it seems they will miss the postseason for the third time in four years.
Bautista reached 30 home runs for the seventh straight season.
Cleveland's coronation as AL Central winners was put on hold as the Chicago White Sox claimed an 8-1 road victory.
Jose Quintana gave up one run in six innings, while Melky Cabrera and Jose Abreu set up the victory by driving in runs in the first inning, while Todd Frazier later connected for his 39th homer of the season.
The Indians' magic number " the aggregate of their wins and/or losses by their nearest rival " to clinching the AL Central is two.
The Los Angeles Dodgers magic number to clinch the NL West is one after crushing Colorado 14-1.
Clayton Kershaw pitched seven scoreless innings and Josh Reddick slugged a grand slam in the seventh.
The Dodgers will wrap up their fourth straight division title with their next win or San Francisco's next loss.
Detroit dropped out of the AL wildcard berths with a 7-4 home defeat at the hands of Kansas City, having led 4-2 in the ninth.
Paulo Orlando hit a tying, two-run double in the top of the ninth and Eric Hosmer followed with a three-run homer for the Royals.
The Tigers, who had won their previous five, are half a game behind Baltimore for the last AL wildcard.
Texas showed no sign of hangovers the day after clinching the AL West, as they won 5-0 at Oakland.
Elvis Andrus, the sole veteran in a youthful Texas batting lineup, hit a pair of two-run homers for his first career multi-homer game.
Texas moved 29 games above a .500 winning percentage for the first time in exactly four years.
The Mets fell behind 10-0 by the fourth inning, then fell short of what would have been the largest comeback victory in team history, losing 10-8 to Philadelphia.
The Los Angeles Angels scored nine runs in the final two innings to win 10-4 at Houston, putting a major dent in the Astros' playoff hopes.
Baltimore reclaimed its hold on the second AL wildcard by downing Arizona 6-1, helped by Mark Trumbo hitting his league-leading 45th homer.
San Francisco blew a six run lead before scoring three times in the 10th inning to salvage a 9-6 win at San Diego and maintain a share of the two NL wildcards.
Miami's Derek Dietrich hit a two-run homer as the Marlins beat Atlanta 6-4, ending the Braves' season-high seven-game streak.
Minnesota beat Seattle 3-2 to leave the Mariners 2-1/2 games off the second AL wildcard, with their playoff ambitions fading.
Cincinnati's Dan Straily continued his mastery of Milwaukee this season, pitching the Reds to a 6-1 win against the Brewers.
This story has been automatically published from the Associated Press wire which uses US spellings