Of all the ways in which the pieces of the Phillies’ roster puzzle haven’t fit together over the last few years, this is the most glaring: Since the start of the abbreviated 2020 season, the pitching staff leads the majors in ground-ball rate, while the defense ranks last in runs saved.

It will be Bobby Dickerson’s job to rectify the latter in order to help the former.

Dickerson, 56, has been rehired as the Phillies’ infield coach, the team announced Monday, replacing Juan Castro, who was let go before the season finale on Oct. 3. Dickerson worked in that role on manager Gabe Kapler’s staff in 2019, then spent the last two seasons as the Padres’ bench coach and third-base coach, a position that was no longer guaranteed after San Diego fired manager Jayce Tingler earlier this month.

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Across baseball, Dickerson is regarded as a top infield instructor. He scored high marks three years ago from Rhys Hoskins, Jean Segura, and other Phillies infielders for his creative drills and attention to detail. In a statement released by the team, manager Joe Girardi said Dickerson came “highly recommended by our players who worked with him in 2019. They loved him.”

The Phillies ranked 28th, 30th, and 26th among 30 teams this season in runs saved at first base, shortstop, and third base, respectively. Didi Gregorius ranked 11 runs worse than the average shortstop; Alec Bohm was 13 runs worse than the average third baseman. It wasn’t a winning recipe, especially considering the ground-ball tendencies of starters Zack Wheeler, Aaron Nola, Zach Eflin, Kyle Gibson, and Ranger Suárez.

“Overall, defensively, we have to get better,” Girardi said recently. “I believe that our defense cost us games this year. I think that range and ball securement is really important, and those will be things that we continue to try to tackle and accomplish.”

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Bohm figures to be a primary pupil for Dickerson, who got credit from Kapler for helping third baseman Maikel Franco. Franco went from 10 runs below average in defensive runs saved in 2018 to one run above average in 2019.

Hoskins also had his best defensive season at first base while working with Dickerson. Hoskins saved three runs more than the average first baseman in 2019 compared to five runs less in 2020 and six runs less this year.

But how much improvement can reasonably be engendered in a veteran such as Gregorius? After a decade in the big leagues, at age 32 in February, he is unlikely to suddenly improve his range.

In spring training, Castro, a former infielder who stayed in the majors for 17 seasons because of his defense, tried to instill a better pre-pitch setup for several infielders, including Bohm and Gregorius. By midseason, Gregorius said he reverted to what he had done in the past.

“They wanted me to do some presets that weren’t working for me, so I told them I’m done with that and went back to my old ways,” Gregorius said in July. “Just one step and get ready. Before, I was trying to jump and I was always out of rhythm.”

In dismissing Castro, Girardi said he would look for an infield coach who could “challenge the players to invest in their training — quickness and first step and the anticipation. You challenge them to get after that this winter.”

But Girardi also noted that the players must buy into it by putting in the work in the offseason.

“If they don’t,” Girardi said, “then usually you don’t see the improvement.”

Bohm is expected to work out at the Phillies’ spring-training facility in Clearwater, Fla., where he lives in the offseason. New hitting coach Kevin Long was planning a trip this month to meet with him. It seems likely Bohm will get a visit from Dickerson, too, considering that the Phillies appear to be committed to him at third base.

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Gregorius hasn’t received such full-throated support from the front office. President of baseball operations Dave Dombrowski said after the season that it’s “not guaranteed that [Gregorius] has been told that he’s for sure the shortstop.”

Dickerson has been an infield instructor with the Arizona Diamondbacks, Baltimore Orioles, Phillies, and Padres. He developed a close relationship with Manny Machado in Baltimore.

The Phillies hired him while they were pursuing Machado and Bryce Harper in free agency, and he moved to San Diego after Machado’s first season there. He had words with Fernando Tatis Jr. during a dugout dust-up between Tatis and Machado during the Padres’ September collapse, according to a report by The Athletic.

Extra bases

Bryce Harper and J.T. Realmuto are finalists for the Silver Slugger at their respective positions. Harper is joined by outfielders Juan Soto, Nick Castellanos, Bryan Reynolds, Adam Duvall, Jesse Winker, and Tyler O’Neill; Realmuto is named with fellow catchers Buster Posey, Will Smith, and Omar Narváez. The awards will be announced Nov. 11.