The Braves sent right-handers Lucas Sims and Matt Wisler and outfielder Preston Tucker to Cincinnati. All three spent time in Atlanta this season but were with Triple-A Gwinnett at the time of the trade.
The trade was announced after the Braves' 5-3 win over Miami on Monday night.
Duvall reacted to the trade in a series of tweets on Tuesday.
It's been a wild 12 hrs. First off I'd like to thank the Reds organization for giving me a chance to play the game that I love. Next, to the fans of Cincinnati, I'd like to personally thank you for making my stay in Cincy a good one. You guys showed a lot of love and I'll never— adam duvall (@aduvall123) July 31, 2018
forget that! Next, I'd like to thank my teammates. You guys made it so much fun to show up to the ballpark everyday and compete. I am going to truly miss you guys! To the trainers, strength coaches and everyone behind the scenes that kept me on the field, I am very grateful.— adam duvall (@aduvall123) July 31, 2018
And last but not least, I want to thank the Braves for adding me to a great team. I look forward to joining you guys, and to help continue the winning ways!— adam duvall (@aduvall123) July 31, 2018
The 29-year-old Duvall has hit 15 home runs with 61 RBIs, but is batting only .205 this season.
Duvall hit 64 homers over the previous two seasons; 33 in 2016 and 31 last season. He was a National League All-Star in 2016.
Duvall was also a finalist for the Rawlings Gold Glove Award in each of the past two seasons.
The Associated Press contributed to this report.