Adams broke a scoreless tie with a sixth-inning double and Ross won his first game since July 4, 2017, when Washington opened a nine-game road trip with a 3-0 victory over Arizona on Friday night.
He was sitting in the dugout when he was informed that he would replace first baseman Howie Kendrick, sidelined by leg cramps.
"I have an activation routine that I do, so I went in the (batting) cage and took some `bp' and warmed up the arm as quickly as possible,"Adams said.
"It is what it is. That's baseball."
Adams, a left-handed hitter, is 12-for-41 with 14 RBI against lefties this season.
"It's something the last couple of years I've been working hard at, and for it pay off, that's good," Adams said.
Juan Soto hit a solo homer in the eighth inning to extend his career-high RBI streak to seven games. He has reached base safely in nine straight, with four homers and nine RBI.
Ross (1-3) gave up one hit and five walks in 5 1/3 innings in his second start of the season, the only hit coming when Young beat out a slow roller past the mound with one out in the fifth inning.
Ross struck out three and permitted only two runners as far as second base, those coming when he walked two with one out in both the second and third innings. Ross and four relievers, including trade-deadline acquisitions Roenis Elias and Hunter Strickland, limited the Diamondbacks to one hit as the Nationals broke a two-game losing streak.
Arizona, playing its first game since trading ace Zack Greinke to Houston for four minor league prospects at the deadline Wednesday, fell 4 1/2 games behind the wild card leaders.
"There are certain games at certain times that leave you scratching your head," Arizona manager Torey Lovullo said. "This was definitely one of them. We get one hit -- our pitcher scratches out a base hit for us."
Elias retired the only two batters he faced after relieving Ross with one out in the sixth inning before leaving with a right leg injury. Strickland struck out two in a 1-2-3 seventh.
Elias grabbed the back of his upper right leg when he pulled up near first base while attempting to beat out a slow grounder to second in the seventh inning. Manager Dave Martinez said it was being treated as a cramp, not a hamstring injury.
"He was told not to swing," Martinez said. "As many times as I could tell him, Spanish, English. He said sorry to me. What I saw out of him and Hunter today was really, really good."
Sean Doolittle pitched a 1-2-3 ninth for his 24th save in 28 attempts. The Nationals entered game with a major league-high 5.90 bullpen ERA.
Young (3-1) gave up three hits and three walks while striking out a career-high nine in his sixth major league appearance, his fifth start. Trea Turner's leadoff single in the first inning was Washington's only hit Eaton doubled in the sixth
Washington manager Dave Martinez spent part of his off day Thursday milking cows at the Arizona Dairy Company, which has a herd of 13,000 cows in suburban east Mesa. "I had to do it just to say I did it," Martinez uttered. "I like to do different things."
Doolittle became the first pitcher to use the Chase Field bullpen cart this season when he entered in the ninth inning. He also used it three times here last season.
HE LONG GOODBYE
Greinke returned to Phoenix on the Diamondbacks' team flight Wednesday, a few hours after he was traded to Houston. It was fine with Lovullo.
He was a great example of what we want an Arizona Diamondback to be," Lovullo said.
He prepared. He brought compete. He would celebrate with the guys. He would hurt with the guys. When I was told he would be on the airplane, I'm like, `good.' I appreciate the fact that he wants to do that."
Lovullo said his final conversation with Greinke "was hard on me."
"I thanked him for being a great teammate and helping me be a better manager. I got a two-arm hug from Zack. It was fantastic," he said.
Nationals: RHP Max Scherzer (rhomboid strain) made 25 throws while playing catch at 70 feet on flat ground Friday, his first throwing session since going on the IL retroactive to July 26. He has several steps to take before he gets on a mound, manager Dave Martinez said, and is unlikely to be activated from the injured list when eligible Monday. "We're going to make sure he's 100 percent when he comes back," manager Dave Martinez said. ... LHP Tony Sipp was designated for assignment Friday.
Diamondbacks: RHP Matt Andriese (left foot contusion) threw 24 pitches in a rookie Arizona League game Thursday and is expected to continue his rehab assignment at Class A Visalia on Sunday . Luke Weaver (forearm strain) played catch at 150 feet Friday.
Nationals: RHP Stephen Strasburg (14-4, 3.26) has won seven straight starts since a 10-3 loss to the Diamondbacks on June 15, when he gave up six runs and four homers) in five innings. He had a 1.14 ERA in five July starts.
Diamondbacks: LHP Robbie Ray (9-7, 3.91), mentioned prominently in trade rumors, was 4-1 with four quality starts and 44 strikeouts in 30 1/3 innings in July. He 0-5 in six career starts against the Nationals.
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