OAKLAND -- Matt Chapman lined a three-run homer just over the left-field wall to cap a five-run fourth and lead the A's to an 9-3 win over the Orioles on Sunday afternoon at the Coliseum.
Down by two entering the fourth, Oakland tied the game when Ryon Healy hit an RBI double and Khris Davis beat Chris Davis' throw home on a Matt Olson grounder. Chapman then hooked a low changeup just over the 330-foot marker in left field, giving the A's the lead with his eighth homer of the year.
"The home run was big for [Chapman]," A's manager Bob Melvin said. "To put together an at-bat like that, which, at the time, was the at-bat of the game. It gives us a little distance and it gives us the lead. There's a big difference with three more runs like that at 5-2, so that was a big at-bat for him."

The offense backed up right-hander Kendall Graveman, who picked up his first win since coming off the disabled list Aug. 3. Graveman went seven innings, allowing two runs on eight hits and one walk while striking out eight.
• Graveman picks up first win since April
"I think that's the best I've actually pitched in a while," Graveman said. "To be able to locate like I did, I did a good job of locating down and away and throwing that fastball a lot and then coming when I needed to, especially with a right-handed lineup like that."

Baltimore starter Jeremy Hellickson allowed six runs in five-plus innings, giving up five hits and walking two. Hellickson threw a season-low 65 pitches in the loss, which drops the Orioles to 2 1/2 games behind the Angels for the second American League Wild Card spot.
"I thought he had good enough stuff," Orioles manager Buck Showalter said. "Just one of those days. We knew Graveman -- once he got his feet on the ground -- he's solid. Both pitchers were using the benefit of a couple inches off the plate. There were a lot of strikes called today that weren't strikes, but both pitchers benefited from it."

Orioles third baseman Manny Machado finished the day a double short of the cycle, going 3-for-4 with a triple in the first and a homer in the eighth to give him a .500 mark (7-for-14) over his last three games. Former starter Chris Tillman entered in the eighth for his first career relief appearance after 194 starts. He struck out two and didn't allow a run in 1 1/3 innings.
• Machado's average has steadily climbed
"Different. It was way different," Tillman said, who is hoping to work his way back into the rotation. "It feels good, though. I feel like it was a step in the right direction. … It was one step closer to getting back."

MOMENTS THAT MATTERED
Two-stepping out of traffic: Down by four in the sixth, the Orioles had a chance to rally when Adam Jones singled and Trey Mancini walked to start the inning. But Graveman got Mark Trumbo to ground into a 6-3 double play before striking out Chris Davis looking to get out of the inning unscathed.
"I thought I had my good stuff toward the sixth and seventh innings, and that's good because you're coming to the meat of the lineup," Graveman said. "I think the health is huge, because in that situation, to have your best stuff when the meat of that order is coming up and you've got a three-run lead is big."

Joyce adds on: A's leadoff hitter Matt Joyce extended Oakland's lead twice, scoring in the fifth when he doubled, stole third and raced home on a sac fly. Then in the seventh, Joyce lined a two-run homer to right-center off of Baltimore reliever Richard Bleier.
You look at the overall numbers, the average maybe not, he's had a really good year for us after a really slow start," Melvin said. "When you can put together at-bats like that off lefties, it allows you, especially in games with a lead, to keep our guys in the game because we have a short bench. After the first three or four weeks of the season, he's really been good for us and held down the leadoff spot really well."

QUOTABLE
"Most of the time we're supposed to have some answers. It's just one of those days. That was a strange … just kind of an Oakland game." Showalter, on Hellickson's struggles after three scoreless innings
"These guys are awesome, man. When you see this team, I get really excited about these guys and the young talent that they have. Obviously going into the offseason, there's some needs that need to be addressed, and we have some time before that happens. But there's a tremendous amount of talent here, and these guys are fun to play with. They're a great group of guys - they're very humble, they work hard, they do everything that you ask of them. I think it's going to be an exciting future for the A's." -- Joyce
SOUND SMART WITH YOUR FRIENDS
Olson faced Orioles closer Zach Britton with two outs in the eighth and crushed an inside fastball for a homer, his third-straight game with a big fly. Olson's the first left-handed batter to take Britton deep since April 29, 2013.
"There's a lot of times where I pick and choose, and maybe look inside if a team is pitching me a certain way," Olson said. "They've been throwing me inside a decent amount, especially the lefties, so I took a pitch and sat on an inside pitch and I got it." 
Melvin added: "I don't even know what to say about the home run off Britton. For a lefty to do that? No one's hit a home run off him this year, let alone a lefty."

WHAT'S NEXT
Orioles: Baltimore moves north for the final series of its 10-game West Coast road trip against the Mariners. Right-hander Kevin Gausman (8-8, 5.21 ERA) takes the mound in a 10:10 p.m. ET Monday contest. He will look to continue his hot streak, having posted a 1.67 ERA in his last four starts.
Athletics: Right-hander Jharel Cotton (5-9, 5.72 ERA) will take the mound as the A's open a three-game series against the Royals at 7:05 p.m. PT Monday. Cotton took the loss against the Mariners in his last start, giving up six runs in six innings.
Watch every out-of-market regular-season game live on MLB.TV.