WEST PALM BEACH, Fla. — His mind goes back to May 8, 2019, to inside Miller Park, straight into a moment he would rather forget. But baseball doesn’t work that way. It is often the bad plays that stick around.

And this one, Adam Eaton admits, was really, really bad.

The Washington Nationals were skidding against the Brewers in Milwaukee. Eric Thames sliced a popup in the first inning, and Eaton took off running. But as he neared the left field line and the ball dropped to earth, Eaton was stuck. He had gone too far and could not slow down. He has had trouble decelerating since he tore his left ACL and sprained his left ankle on the same step in 2017. So he shuffled into the dirt, a double bounced behind him, and, helpless, he turned to watch the ball find the stands.

“It wasn’t good last year,” Eaton said of his defense. “Honestly, at times it was miserable.”

Off the top of his head, he counts four other plays that unfolded like that. The common thread was an inability to slow down how he used to, before his left leg became a nagging problem. The takeaway, when he reviewed the season, formed his biggest goal for 2020: Get much better in right field, his primary position, and give the Nationals baseball’s best defensive outfield.

Juan Soto and Victor Robles were Gold Glove finalists last season. Eaton used to be in that company — in 2014 and 2016 — but is now trying to break habits he formed after the injuries. It is his focus for February, and it will be his focus in March, and that won’t change until his brakes are finally fixed.

“Just trying to keep up with them is a chore,” Eaton, 31, said of Soto and Robles. “I feel like we can each improve on defense, in some shape or form, but I have much farther to go than they do.”

Every defensive statistic went against Eaton in 2019. Major League Baseball’s Statcast uses “outs above average” to quantify in a single number a player’s range, defensive skill and the difficulty of plays made. Robles finished the year with 23, which led the major leagues. Eaton, in a stark contrast, finished with one. FanGraphs’ all-encompassing defensive metric rated Eaton well below average. So did Baseball Reference’s way of measuring defensive wins above replacement.

But Eaton believes this is correctable and even part of a four-year recovery cycle. In 2017, he missed all but 23 games after the ACL tear and ankle sprain. In 2018, he was compensating for lingering pain and, as he put it, “just trying to get by.” That led him to decelerate by hopping on his right leg while swinging his left foot out in a semicircle. The maneuver kept weight off his left leg and was a more comfortable way of slowing down. Yet in 2019, when the leg felt better, the ­hopping and swinging became muscle memory.

He wants to get back to planting his left foot in the ground to stop. It is the difference between tapping the brakes and slamming them. And in the field, that is the difference between excelling and making mistakes.

“It’s a vicious cycle,” Eaton explained Sunday. “At first, you’re trying to cheat because it hurts, and because your gait is [expletive] up. The next year, you keep doing it because it’s what your body knows. Then the next year, you can hopefully get back to your normal self. That’s where I am now. I’m getting back to normal.”

Normal began this past ­August, when the pain eased. Eaton saw an uptick in power at the plate, and he felt better in right field. But he can’t wait for spring to end, and the summer to dwindle, for that to happen this year. That’s why the next five weeks will center on his defensive mechanics.

Eaton plans to log a few more innings than usual before Opening Day and otherwise use workouts to track balls to the line, to the corner and toward the wall. His locker in West Palm Beach is right next to Thames’s, who signed with the Nationals in January. Thames has mentioned that play in Milwaukee more than once, and he jokes that Eaton gifted him a double. It’s a fact that Eaton won’t deny.

“I hate thinking about that, but you also have no choice,” Eaton said. “If you take away that play, the four other ones, you start to put together a decent defensive season. You start to get back to what you were in 2014, maybe, when your legs did what you asked. You go in the right direction.”

By talking to Eaton, it’s clear how bothered he is by a half-dozen instances across an eight-month stretch.

“You wouldn’t want to be inside my head,” Eaton added with a laugh. “You’d start to wonder, ‘How the hell does he live like this?’ ”