This story was excerpted from Justice delos Santos’ Pirates Beat newsletter. To read the full newsletter, click here. And subscribe to get it regularly in your inbox.

In a clubhouse filled with big, lively personalities, Liover Peguero might hold the title of the biggest, the liveliest. He’s living his dream, and he’s content to have fun while doing so. But in the not-so-distant past, Peguero navigated a time when he had too much fun, a time when baseball was more of a game and less of a craft, a job, a responsibility.

Peguero, 45 games into his Major League career, still carries a youthful exuberance when he enters a ballpark. It’s who he is. Over the past year, he’s found a balance.

“If you don’t grow up quickly in baseball, you’re going to [plateau],” said Endy Rodríguez. “You don’t want that. He understands that. … I think growing up as a player, as a person has been the best thing for him this year.”

In 2022, Peguero didn’t take the step forward that many expected. With Double-A Altoona, he was a subpar hitter (88 wRC+) and a subpar defender (31 errors). Peguero saw Rodríguez, Quinn Priester, Carmen Mlodzinski and Nick Gonzales begin this season with Triple-A Indianapolis, but he remained in Altoona.

“It gives you more motivation,” Peguero said. “It made me want to work harder.”

Working harder wasn’t just a matter of taking more swings, fielding more grounders. It was also a matter of growing as a person. Peguero recalled Gary Green, Altoona’s bench coach, telling him that he could play in the Majors but needed to be stronger mentally. Specifically, Peguero needed to refine his ability to be even-keeled.

“I’m going to be honest; two, three years ago, I used to be a very up-and-down person,” Peguero said. “That was one thing that was affecting me a lot. If I made a good play, I was like, ‘Oh, let me scream, let me be happy.’ I didn’t recognize that at the time until I had multiple conversations with people older than me, people who have been in this game for a lot of time.”

Peguero credits Green, Callix Crabbe (Altoona’s manager), Blake Butler (Altoona’s development coach) and Kieran Mattison (Altoona’s manager last season) with pushing him forward and, when necessary, providing tough love. Crabbe, in particular, imparted upon Peguero that he should be like a rolling hill, one that does not get too high or too low. Crabbe also emphasized to Peguero that he can’t take pitches or at-bats off at the Major League level, a habit Peguero has since kicked. 

“We worked really hard on a personal level, day in and day out,” Crabbe said. “We talked a lot about developing better mental processes. I'm definitely not taking credit for the entire experience. It was a full-staff effort.”

Peguero’s coaches and teammates have witnessed his maturation firsthand. Rodríguez said that Peguero has “grown up.” Ke’Bryan Hayes noted that Peguero “still is who he is,” but exhibits a seriousness during the workday. Manager Derek Shelton assessed that Peguero maintains a fun, vibrant personality but knows “there’s an attention to detail you have every day to be a solid Major League player.” The best testimonial, however, came from infield coach Mendy Lopez, who recalled a conversation he had with Peguero during Spring Training. 

“He told me, ‘Mendy, I was a kid last year. This year, I know what I can do and what I can’t do. I used to have too much fun. Now, I’m not that guy. I have to be able to focus when focusing is required. I was not focused; I was just trying to have fun during the game. Not this year,’” Lopez recalled. “To me, that was an ‘Ah ha’ moment. I was like, ‘Wow.’ He’s very young to have that type of mentality, and I’m glad he has it.”

That mentality has landed Peguero in Pittsburgh, where he’s played his way into a starting role. Despite starting the year with Altoona, Peguero earned a promotion to Triple-A Indianapolis after a blistering June (.969 OPS) with Altoona, then spent just seven games with Indianapolis before being promoted. 

Peguero, the team’s youngest position player, has exhibited flashes of power (seven home runs) and speed (four steals) amidst rookie struggles that provide a glimpse into his upside. His growth on defense, specifically, has been especially impressive. A year removed from those 31 errors, Peguero has been worth two Outs Above Average, a product of making plays like this…

... and this ...

... and this.

“People don’t realize how dynamic he is,” Crabbe said. “I was talking to Rickie Weeks a couple weeks ago. Him and I played together. I told Rickie -- I said this in a fun way -- ‘Peguero is potentially a better version of you.’”

Crabbe evaluated that Peguero runs like Weeks and impacts the ball like Weeks, adding that Peguero will likely defend better than Weeks because of his ability to play shortstop in addition to second base. For the flashes, Peguero understands there is more work to be done. 

“I’m always the type of person that never has enough,” Peguero said. “Especially in this game, you can’t feel comfortable. … Whenever you feel like you got it, that’s when you have to recognize that you don’t got it.”

As things stand, Peguero is a favorite to start at second base alongside shortstop Oneil Cruz, who was officially ruled out for the remainder of this season. If the Pirates are to make the postseason next year, they’ll need contributions from Peguero, who turns 23 in the offseason. To Lopez, Peguero isn’t shying away from that pressure. 

“He wants to be the man,” Lopez said. “He knows that by being the man, there’s a lot of responsibility that’s going to come his way. He’s excited about that responsibility. Yes, he needs to keep working. Yes, he has a lot of room to get better. But I think he’s so passionate about being the man. … The way he sees [Bryan] Reynolds, the way he sees [Andrew McCutchen], the way he sees Hayes, he wants to be that type of guy. He’s not messing around. He’s come to stay and he’s come to make a difference. He’s not afraid at all to be in front of the line.”