PHOENIX -- Just three batters into his first career start, Anthony Banda got his "welcome to the Majors" moment Saturday night at Chase Field. After getting two quick outs, Banda surrendered a towering solo homer to Bryce Harper that started the scoring for the Nationals en route to a 4-3 win.
Sean Doolittle worked the ninth for his second save in as many chances with the Nationals, allowing an unearned run on Paul Goldschmidt's pinch-hit sac fly but striking out Ketel Marte with the potential tying run at first base.
"It was a great atmosphere," D-backs manager Torey Lovullo said. "Unfortunately, we just came up on the wrong end of things. Anthony Banda had a tremendous outing against a very offensive team. I felt like he was making pitches, doing his job, being consistent with his execution."

Although Banda settled in and held the Nationals scoreless over the next four innings, it wasn't enough as Washington erupted for three runs in the sixth. Chris Heisey, Harper and Ryan Zimmerman all had extra-base hits in the inning as the Nationals sent eight batters to the plate.
• Harper finds 2nd sweet spot with less stride
"We had pretty good at-bats," Harper said. "That's a young guy out there that throws the ball really hard, has good stuff, has good command. He's going to be really good in the next couple years for sure. So just we got him this time and got a few runs up there and won the ballgame."

The D-backs drew even at 1-1 in the first on a two-out RBI double from Chris Iannetta to score A.J. Pollock from first, and they tacked on a second run in the sixth when Pollock tripled and then scored. Washington starter Tanner Roark held the D-backs to three hits and struck out 11 in seven innings to record his first double-digit strikeout performance of the season. This was perhaps his best outing of the year and a second consecutive encouraging start for Roark, who is finding his groove after a rocky first half.
"He doesn't look worried," Nationals manager Dusty Baker said. "He was looking worried before… It looks like Tanner's back, big time. We needed to win that game for us and for him. It's a good feeling when one of your guys has that feeling. You get that feeling. The whole team gets that feeling."

MOMENTS THAT MATTERED
Doolittle shuts the door: The D-backs brought the potential winning run to the plate in the ninth after Jake Lamb scored on Goldschmidt's sac fly to cut the lead to 4-3. But Doolittle erased any ideas Arizona had of stealing its eighth walk-off win of the year.
"What can happen in those situations, the game can really speed up on you," Doolittle said. "Once you start getting guys on base, the crowd, the energy of the stadium can kind of take over. And it speeds everything up. So you have to be mindful enough to step off the mound, slow the game down a little bit, kind of press reset and go back through the advance report, remind yourself what you've got to do, how you're going to start this at-bat by going strike one, and then go from there."
Doolittle got Chris Owings to fly out to the right, then struck out Marte with a 97-mph fastball to end the game.
"I was proud of the way our guys fought," Lovullo said. "We weren't very offensive, however, we created several opportunities throughout the course of that last inning that allowed us to have moments where we were one swing away from winning the game, getting back in the game. It's just such an emotional letdown when it happens the way it does, when the crowd is behind you."

Heisey sparks hit parade: In the sixth, Heisey hit a one-out triple to left that sparked the three-run inning. The ball had just a 38 percent chance of landing for a hit, according to Statcast™, and it caromed into the left-field corner and allowed him to leg it out to third. Heisey scored one batter later on Harper's ground-rule double, and Zimmerman followed with another double in the next at-bat to push Washington's lead to 4-1.
"[Banda] got a little nicked up against a couple of really good hitters," Lovullo said, "some guys that have proven track records of attacking pitchers and having a lot of success. He did a really good job stepping in at a moment's notice."
Heisey injured his groin on the triple, which might force the Nationals to make a roster move for an outfielder before Sunday's series finale.

QUOTABLE
"He has guts. You see he came right after Goldy, and not many people come at Goldy like that." -- Baker, on Doolittle

SOUND SMART WITH YOUR FRIENDS
• Harper extended his hitting streak to a career-high 15 games, during which he is batting .458 with seven home runs.

• In the sixth inning, Zimmerman smashed his 361st career double to pass Tim Wallach for the most career doubles in franchise history.

WHAT'S NEXT
Nationals: The Nats wrap up their nine-game road trip with Sunday's series finale at Chase Field against the D-backs. Right-hander Stephen Strasburg will take the mound after seven innings of one-run ball with 11 strikeouts in his last outing against the Reds. First pitch is at 4:10 p.m. ET.
D-backs: Arizona closes out the series with left-hander Robbie Ray on the mound Sunday at 1:10 p.m. MST. Ray will be in search of his second win out of the All-Star break. He is 3-1 with a 2.45 ERA in his last four home starts. Preview >>
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