I don’t think it would be unfair to categorize Adam Duvall as a free swinger. In his two full-time seasons with the Reds, he finished in the NL’s top ten for home runs and strikeouts. He was swinging hard, pretty much all the time.
I have a pretty simple theory on Duvall, or players like him. From a baseball skill perspective, compared to other MLB players, Duvall does one thing well on offense: he can hit the ball hard. He’s not fast, he doesn’t have a particularly good eye at the plate, his hit tool (ability to make consistent contact, perhaps) isn’t advanced. Anyways, my non-researched theory is that extreme one-skill players will fall off the cliff quicker than more balanced players.
This is the part of the article where you ignore that I’ve not presented any evidence for this theory save for the one player we are about to discuss, who conveniently has a stat line that unreservedly supports my heretofore undiscussed thesis.
Most of Duvall’s metrics stayed fairly consistent from 2016-2018. His strikeout rate stayed steady, his walk rate improved some in 2018 but not enough to suggest that his approach was different, and his fly ball to ground ball ratio stayed pretty consistent. What changed is that the number of fly balls that turned into dingers went from 15% (2016) to 13% (2017) to 11% (2018). Still good by the end, but not good enough to make up for the limited skills elsewhere. The “why” behind all that is where the interesting story lies. Perhaps pitchers approached him differently: I can see that opposing pitchers threw slightly more breaking pitches and slightly fewer strikes as his career progressed. Maybe there’s a tipping point situation in there somewhere. Or maybe Duvall’s bat speed declined just enough to show up in a sizable way.
We don’t truly know, but the resulting trends suggest that Duvall is probably close to done: 106 OPS+ in 2016, 99 OPS+ in 2017, 81 OPS+ in 2018. And that’s before the Reds traded him to the Braves. In Atlanta, Duvall closed out the season on a 7-for-53 run that included just one extra base hit and one walk.
Given all that, it’s impressive that Duvall’s defense has been good enough to keep him on the right side of replacement level, especially at a non-premium defensive position.
Over parts of four seasons, Adam Duvall played in 439 games with the Reds, hitting .235/.297/.469 (98 OPS+), with 84 HR and 272 RBI. At the 2018 trade deadline, Duvall was sent to Atlanta for Lucas Sims, Preston Tucker, and Matt Wisler. On the back of his 2018 season, Duvall went from #236 on the Reds all-time list to #203.