Nathan and Chamberlain were brought in to solidify a Tigers bullpen that struggled last season. Chamberlain, who foundered with the Yankees in 2013, had a strikeout. Nathan, who saved 43 games for Texas last year, struck out two. It was the Detroit debut for both.
''I liked what I saw from all of our pitchers today,'' rookie manager Brad Ausmus said. ''They threw strikes.''
Rick Porcello started for the Tigers and allowed one run in two innings. He struck out three.
Heyward's shot cleared the palm trees beyond the right-field fence.
''I heard something hit the roof way out in right field and I figured out who hit it,'' Medlen said.
Braves: Medlen, who won a team-high 15 games last season, allowed two hits and struck out one. He said he is just working on mechanics for now.
''I didn't hurt anything, so that's good,'' Medlen said. ''I mixed my pitches and, when I missed, it was down, so that's exciting.''
Tigers: Porcello gave up one hit and struck out three while walking one. He was 13-8 with a 4.32 ERA last season in 29 starts.
Braves: Gerald Laird came out after the first inning with a lower back strain. The catcher said he got hurt while grounding out. He caught the first inning but said his back was bothering him so much he allowed a passed ball. Laird said he was day to day.
Atlanta left fielder Justin Upton missed his second straight game with tenderness in his right side. He is also day to day.
Tigers: Alex Avila caught four innings and went 2 for 2 in his first game after sitting out several days with back spasms.
Heyward's home run soared over the right-field fence, a grove of palm trees and finally landed on a building that houses the Tigers' batting cages.
''I had the perfect swing and I just raked it,'' said Heyward, who hit 14 homers last season. ''Doing it off a left-handed pitcher made it even better. My swing is taking care of itself.''
OUT OF ORDER
Tigers center fielder Austin Jackson batted sixth, an unusual slot for him, but Ausmus said Jackson could bat in any number of places this season and didn't plan to set anything in stone yet.
''We plan to try a few different things with him,'' the manager said. ''Things will get mixed up. If he bats leadoff, it isn't like he's never done that before.''
Jose Iglesias led off for the Tigers.
MORE FROM THE BULLPEN
Bruce Rondon entered spring training last year with a shot to become the Tigers' closer, but was one of the final cuts before the team went north. With Nathan entrenched as the closer now, Rondon will be a setup man if he makes the club. Rondon went 1-2 with a 3.45 ERA in 30 games after he was called up last season and struck out 30 batters in 28 2-3 innings. He regularly hits 100 mph with his fastball.
In one inning against the Braves, he retired all three batters he faced.
''I don't care how hard he throws,'' Ausmus said. ''If he gets them 1-2-3, I will take it.''