Alex Avila belted the tie-breaking grand slam in the sixth inning off Stephen Strasburg, and the Detroit Tigers earned a 5-1 win over Washington in the opener of a two-game series.
Anibal Sanchez (9-7) allowed five hits and a run over seven innings to move his career mark to 9-1 against the Nationals.
Andy Dirks drove in the other run for the AL Central leaders, who have won four in a row and eight of their last nine games.
After the contest, the Tigers were involved a blockbuster 3-team deal with the Chicago White Sox and Boston Red Sox. The Tigers sent right-handed pitcher Brayan Villarreal to Boston. Outfielder Avisail Garcia ended up going from the Tigers and went to the White Sox. Detroit also acquired shortstop Jose Iglesias.
As part of the deal, former Cy Young Award winner Jake Peavy went from the White Sox to Boston.
Ryan Zimmerman had the lone RBI for the Nationals, who were coming off three straight wins against the Mets.
Strasburg (5-9) gave up six hits and fanned seven over seven frames. The right-hander has yielded at least five runs in two of his last four starts and is 0-3 in that span.
The Nationals had a pair of runners in scoring position in the sixth, but Denard Span grounded out to end the inning.
Prince Fielder singled and Victor Martinez doubled with one out in the bottom of the frame. Jhonny Peralta walked. With two down, Avila clubbed a 2-1 pitch over the wall in right field.
"I think he's been a little more aggressive at the plate," Tigers manager Jim Leyland said.
It was Avila's first career grand slam. It was also the first time in Strasburg's career that he's allowed a homer with more than one man on base.
"I thought he pitched great. He just made that one bad pitch there," Nationals manager Davey Johnson said.
Jose Veras, who was acquired in a trade from Houston on Monday, retired the side in order in the eighth. Joaquin Benoit worked around a single in the ninth inning to close the contest.
Bryce Harper tripled off the wall in right field to start the game, and with one out Zimmerman bounced a single into center field. Ian Desmond grounded into a force play to leave runners at the corners.
Dirks double to left to drive in Fielder in the fourth.
The Nats have lost six of their last eight road games ... Washington won both meetings with Detroit back in early May after losing the previous six meetings between the clubs ... The Tigers have outscored their opponents 29-6 during their winning streak.