The right-handers, acquired just before the July nonwaiver trade deadline, will oppose each other Saturday night in the middle game of a weekend series between the Braves and Pirates at SunTrust Park.
Gausman, acquired from Baltimore, is 4-1 and has a 1.69 ERA in five starts for the Braves and worked eight scoreless innings in a victory over the Pirates in Pittsburgh.
Archer, obtained by the Pirates from Tampa Bay in what was considered a more significant deal, is 1-2 with a 6.45 ERA in five starts for his new team and had to leave a loss to the Braves in Pittsburgh after four innings when he tweaked his left leg while batting.
The success or failure of the pitchers has mirrored the results of their teams, with the Braves (74-60) holding first place in the National League East and the Pirates (66-69) slipping way behind in the NL Central.
Atlanta's lead in the NL East over Philadelphia is down to two games, though, after the Pirates, swept by the Braves in Pittsburgh just over a week ago, won the series opener 3-2 on Friday night in Atlanta.
Gausman, who was 5-8 with a 4.43 ERA for the Orioles before the trade, has won four straight starts since losing his debut with the Braves and has gone eight innings twice to give the Braves' bullpen a needed break.
The former No. 4 overall draft pick has allowed just 21 hits in 32 innings for the Braves and has 22 strikeouts and seven walks.
Gausman, 27, gave up four hits against the Pirates on Aug. 21 in Pittsburgh, struck out five and walked two.
"Any time you change anything as a major leaguer, there's always a big question mark in your mind," Gausman said. "There was a part of me that was a little hesitant, but I just jumped headfirst right into it."
Gausman, who was 0-1 with 10 earned runs allowed in 10 2/3 innings against the Pirates in two starts for Baltimore, has not only changed teams and leagues, but abandoned the windup to go solely from the stretch.
"Overall, I think it made everything better," he said. "I think I'm more consistent. Fastball command has definitely been a lot better. It's easier to throw the ball (in) the zone when I want to."
Archer was 3-5 with a 4.31 ERA in 17 starts before the trade to Pittsburgh, and the Pirates thought the 29-year-old was ready for a late-season turnaround and success in the future.
Instead, Archer has struggled even more. He has lasted less than five innings in three of his starts for the Pirates and failed to make it to the sixth in the other two.
Archer was tagged for six runs in the third inning during a loss to Milwaukee in his most recent start, surrendering five consecutive hits that included a pair of two-run homers.
"I know I keep saying it, but my stuff is good, everything feels good. I just need to execute at a higher level," Archer said after the loss to the Brewers. "A six-run inning is inexcusable."
The only run Archer gave up against the Braves came in the first inning came on a two-out single by Nick Markakis, but he had to leave early because of the mishap batting -- something he wasn't used to doing with the designated hitter.
Archer is 0-for-6 with four strikeouts for the Pirates. Gausman, another former American Leaguer, is 1-for-12 for the Braves and has drawn two walks to go along with three strikeouts.