Andrew Stevenson, who had recorded a total of 10 career hits in 42 previous games, went 4-for-5 with two doubles. He also drove in four runs for the Nationals, whose 15 runs equaled their most since they beat the Cincinnati Reds 18-3 last June.

The Nationals were able to salvage a 4-5 trip by snapping a four-game losing streak and out-hitting the Giants 18-7.

Scherzer (5-1) became the National League's first five-game winner, allowing five hits and two runs. He walked two and struck out 10.

Seeking a fourth consecutive win, the Giants countered a three-run Nationals first inning with a run in the second on back-to-back doubles by Brandon Crawford and Nick Hundley.

Adams then followed a two-out intentional walk to Bryce Harper with his third career home run off Giants starter Jeff Samardzija for a 6-1 lead in the top of the fourth inning, allowing Scherzer to coast from there.

Samardzija (1-1), who pitched five shutout innings in his season debut Friday against the Los Angeles Angels, was pulled after Adams' homer. He allowed six runs and eight hits in 3 2/3 innings. He walked three and struck out three.

Stevenson, who had a two-run double in the three-run first, helped Washington pad its lead in the sixth inning with a second run-scoring double. His four RBIs were double his previous career total of two.

Adams, who had a single and a double to complement his homer, combined with Stevenson for seven hits, 10 RBIs and four runs.

Trea Turner had a career-high-tying five hits and two RBIs, and Adrian Sanchez added a pair of hits for the Nationals, who return home to begin a 10-game homestand Friday against the Arizona Diamondbacks.

Five San Francisco pitchers combined to give up the season-high run total.

Brandon Belt had a triple and a single, and Pablo Sandoval a double and a single for the Giants, who had a streak of seven straight games with a home run snapped.

--Field Level Media