The homer moved Howard into a tie with Albert Belle for 69th place on the all-time home run list. Both sluggers hit 381 home runs.
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"I've always loved coming down to Atlanta, playing down here," said Howard, who is tied with Johnny Bench for the most homers (52) against the Braves since the franchise moved to Atlanta in 1966. "It's been a great field. It's been one of those stadiums where I've been able to have some success."
The slam was a high, arching shot that landed just over the right-field wall. The ball traveled a projected 348 feet, according to Statcast™. It measured the ball's launch angle at 45 degrees, making it the sixth-highest recorded launch angle in baseball this season.
Howard is entering the final week of his Phillies' career with the organization planning to exercise a $10 million buyout on a $23 million club option for 2017. But Howard said he is not getting misty-eyed thinking about it.
"I savor every home run, period," Howard said. "You guys are looking at it the way you guys are looking at it. I just really stay in the moment. I don't really try to focus on any of that stuff."
Todd Zolecki has covered the Phillies since 2003, and for MLB.com since 2009. Follow him on Twitter and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.