A few hours before most games, when Alec Bohm is in the Phillies lineup and especially when he isn’t, infield coach Juan Castro stands at home plate with a bucket of balls and hits grounders to the young third baseman. One after another, in the echo of an empty ballpark — thwack ... thwack ... thwack — Castro drills Bohm on positioning, footwork, reactions, and more.

There’s a lot to cover.

Last weekend, during one of their early-afternoon sessions at Citizens Bank Park, Bohm shuffled his feet to chase a ball to his left but was unable to coil his 6-foot-5 body to corral it. He kicked the ball, then reached down to retrieve it and chucked it clear over the fence and into the left-field bleachers.

“He’s one of those guys that is emotional and shows it,” Castro said the other day before the Phillies played in Arizona. “He needs to work on that, of course. But as soon as he starts understanding a lot of these things, I believe he’s going to grow up faster.”

If anything, this season has revealed how much growing up Bohm still has to do.

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Entering this weekend’s series in San Diego, the 25 year old was batting .248 with a .305 on-base percentage, seven home runs, and a .651 OPS in 110 games. He had the second-most errors (15) and fewest defensive runs saved (minus-11) among third basemen. Overall, he ranked as one of the least valuable everyday players in baseball, only one-tenth of a win better than replacement level, according to Fangraphs.

Bohm hasn’t concealed his frustration either. He often stalks around the batter’s box when he’s upset with himself or an umpire’s strike zone. He can appear exasperated after being robbed of a hit and hangdog in the dugout. And Castro concedes that Bohm tends to violate the age-old baseball commandment of not lugging his disappointment at the plate into the field.

“Guys want to do good all the time, right? And I don’t blame Bohm because he’s competitive,” Castro said. “Of course at times you have to control things. In this case, if he’s not hitting good, sometimes he takes the hitting to his defense. That’s one of the things I always address. As soon as we cross those lines into the field, that’s defense.”

It’s all such a stark contrast to last season, when Bohm appeared so unflappable en route to finishing as runner-up for National League rookie of the year. As always, though, perspective is required. Bohm’s first season was a seven-week adrenaline rush within a 60-game schedule, barely enough time to experience the depths of a major-league slump at the plate. Though technically not a rookie this season, Bohm is really still a rookie.

The Phillies have mostly stuck with him as he learns on the job. A case could have been made to send him to triple A during a 12-for-73 funk in May or a homerless drought that lasted for 184 plate appearances. Instead, he started 81 of 88 games before the All-Star break.

“Development comes in different forms,” general manager Sam Fuld said. “Getting repetition at triple A, that’s a form of development. Another form of development is dealing with adversity at a high level and the stress that comes with not knowing whether you’re going to play every day. I think Alec’s going to learn from this experience.”

But Bohm’s defensive struggles have become too much for manager Joe Girardi to bear. Bohm made two errors Aug. 6 and another in the next game. Four nights after that, while filling in at first base for injured Rhys Hoskins, Bohm ranged for a ball to his right that went off his glove for an error that was later erased.

Given the high percentage of ground balls induced by many Phillies starting pitchers, Girardi put Bohm on the bench for six consecutive games in favor of utility man Ronald Torreyes at third base and Brad Miller at first. Girardi referred to it as a “reset” because it afforded Bohm more opportunity for intense pregame work with Castro.

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“I do that every day, regardless,” Bohm said before a game in Arizona. “It’s no different. I prepare the same way whether I’m playing or not.”

Maybe so. But the sessions with Castro represent Bohm’s path back to the lineup. Otherwise, with the Phillies unlikely to send him to triple A now, his role down the stretch will be as a pinch-hitter and occasional starter against left-handed pitching.

Castro cautioned that Bohm won’t improve overnight. And Bohm’s problems aren’t new. There were doubts about his ability to stay at third base when the Phillies drafted him third overall in 2018. The organization’s top decision makers lauded his worth ethic, but they also knew Bohm’s size would be an obstacle. Kris Bryant and Troy Glaus are the only players 6 foot 5 or taller with at least 200 games at third base in major-league history.

“There’s guys that can be tall, but they can also bend over, get lower,” Castro said. “There’s some guys that cannot do it very easy. They have to work at it more. With Bohm, I want him to understand according to his body what he’s capable of doing. I know it’s hard for him to stay low all the time.”

Lately, Castro said he has focused on helping Bohm to improve his reactions at third base. Castro said there are “probably eight angles” at which a ball can be hit to a third baseman, and there’s not always time to get into the ideal position to make a play.

“I want his first reaction to be the right one,” Castro said. “We have different angles at third base, so he has to learn to understand which one he’s going to take when the ball gets to him. That’s some of what we’ve been doing.”

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Castro said Bohm has also been working with the strength and conditioning staff to help him stay lower to the ground in his defensive stance.

But what happens when three years of work at a position doesn’t yield tangible results? At what point do the Phillies begin thinking of Bohm at another position, such as first base?

“I’m a big believer that, if you continue to work the right way, there’s always room for you to continue to get better,” Castro said. “The decision later on, if he moves [positions] or not, I don’t know. But I’ve seen him from the beginning of 2019 to now, and he’s been making strides.

“It’s going to take time. Little by little. It’s baby steps.”