Australian men's No.1 de Minaur had his second taste of success in the Georgia capital, beating American Jenson Brooksby to continue his run of fine form.
De Minaur, who won the Atlanta Open three years ago, triumphed over Brooksby 6-3 6-3 on Sunday to lift the ATP 250 tournament trophy once more.
On the back of the victory he's set to jump nine places in the world rankings to 21, which bodes well for the looming US Open.
When he won at Atlanta in 2019 he went on to reach the fourth round of the New York major, which begins at the end of August, before making the quarter-finals the following year.
It's de Minaur's first title since June last year at Eastbourne, and his sixth ATP Tour title overall.
De Minaur had to work hard to reach the decider, rallying from a set down in the quarter-finals and the semi-finals, but the gritty Australian persevered when under pressure.
"It was great to get another title under my name - it's my sixth and not a lot of people have been able to do that, so I feel great," said de Minaur, who this year reached the second week of Wimbledon for the first time.
"I feel great about my game. I've put a lot of work in, so it's great to see the hard work being rewarded."
The final was a clash between two of the ATP Tour's best defenders, but it was de Minaur's attacking play that proved critical as he clawed past the home favourite in 91 minutes.
"I knew coming in it would be a very tactical, chess-like match that we were going to both play," the third seed said.
"I'm happy I was able to execute my game plan and get the win but it was a very tough match.
"Plenty of times it could have gone either way and even though the scoreboard was three and three, it felt very, very tight."
Australian Open doubles champions Kyrgios and Kokkinakis - also known as the Special Ks - were also celebrating after winning an all-Aussie doubles final.
Despite pulling out of the singles with a knee complaint, Kyrgios teamed with his good friend to score a 7-6 (7-4) 7-5 victory over Jason Kubler and John Peers.
The second seeds, who wrapped up a three-set win in a rain-delayed semi over Americans Rajeev Ram and Jack Sock earlier in the day, clinched their second tour-level title as a team in 94 minutes.
It was 26-year-old Kokkinakis' third career ATP doubles title - his first outside Australia - and also a third ATP doubles crown for 27-year-old Kyrgios, who maintains his unbeaten record in tour-level doubles deciders.
The pair's 2022 season record now stands at 13 wins from 15 matches.
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