The three-game interleague series begins on Friday at SunTrust Park.
Baltimore will start right-hander Alex Cobb (2-9, 7.14) against Atlanta left-hander Sean Newcomb (8-2, 2.70) in the series opener.
The Braves (43-30) split two games at Toronto and return home having won seven of their last 10 games. Atlanta has a three-game lead over Washington in the National League East.
The Orioles (21-52) have lost eight of their last 10 games. They dropped two of three games at Washington, although all of the games were within three runs.
Newcomb has made enjoyed a breakthrough season in his second year in the majors. Newcomb has posted two scoreless starts over his last three appearances, most recently on June 16 against San Diego. He struck out seven and allowed two hits in that six-inning start, which he won. That was a bounce-back for the southpaw, who had allowed five runs in 5 1/3 innings against Los Angeles in his previous start.
"After you have a good one, you've got to be able to clear it and look forward to the next one," Newcomb said. "You've got to treat each start as kind of a new thing, whether you had a good one or a bad one. That allows you to go out fresh every time."
Newcomb leads the team in wins and has allowed two or fewer runs in ten of his 14 starts. He has never faced the Orioles.
"It's good to see that maturity and confidence in him now," Atlanta manager Brian Snitker said. "There's no panic. I love how he stays pitch-to-pitch during a game. It's just a young pitcher who is confident in what he's doing and has faith in himself."
Cobb has made five quality starts in 12 previous outings but has not pitched well in his last two starts, both losses. He allowed five runs in seven innings against Miami on June 16 and was rocked for nine runs in 3 2/3 innings against Toronto in June 10.
"Being out there and feeling comfortable is such a thing you take for granted," Cobb said. "I'm just really comfortable where I'm at. I'm able to execute a high amount of pitches. That's going to lead to some success."
He has one career start against the Braves in 2012. He allowed two runs in seven innings and struck out six in earning the victory.
With the series in Atlanta, Baltimore will not be able to use a designated hitter. That may be OK with Mark Trumbo, who is hitting .349 (15-for-43) in 13 games playing in the field, compared to hitting .233 in 27 games as the DH.
Atlanta first baseman Freddie Freeman has been among the league leaders all season. He leads the National League total bases (162) and is second in on-base percentage (.420) and slugging percentage (.579). His 93 hits are tied with teammate Nick Markakis for the league lead. His .332 batting average is second only to Scooter Gennett's .336 mark.
The Orioles are expected to get slugger Chris Davis back in the lineup on Friday. He has missed eight games while making offensive adjustments after hitting .150 with 86 strikeouts in 57 games.
"I'm really looking forward to getting him back on the field," Baltimore manager Buck Showalter said. "I'm really looking forward to getting the impactful player he's capable of being."