The Red Sox drafted Triston Casas as the rare high schooler who already possessed big-league size at an imposing 6-foot-4, 238 pounds.

It turns out he's still growing.

The team's top prospect recently stopped by Fenway Park, and the team's first order of business should be updating his bio.

Not only has Casas added bulk, but he's taller, too. A week after his 20th birthday, Casas now stands 6-foot-5 and weighs 255 pounds. To put this in perspective, he's only an inch shorter and already 10 pounds heavier than Yankees behemoth Giancarlo Stanton. If he's got any growing left in him, he could rival Yankees slugger Aaron Judge, all 6-foot-7 and 282 pounds of him.

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"I just turned 20, so I'm still growing into my body," Casas said. "I'm not putting any limits on my size. I'm not sure how much more I might grow. It's been weight training, nutrition, a combination of a lot of things. It's mostly natural. It's my genes. There's no secret formula for it."

Casas noted that his father is also 6-5 — "he's a little bigger than me in terms of roundness" — and that his mom stands about 5-9, "so she's not tiny."

Good genes are only half the battle, though, and Casas is proving himself to be the team's most exciting prospect. The first baseman recently checked in at No. 70 on Baseball America's top 100 list, making him the highest-ranked Red Sox farmhand, five spots ahead of Bobby Dalbec.

 

He put up numbers at two levels of A ball last year that certainly jump off the page for a 19-year-old, hitting .256 with 20 homers and 81 RBIs in what was effectively his pro debut. Drafted 26th overall in the first round of the 2018 draft out of Plantation, Fla., Casas tore a thumb ligament just two games into his career at short-season Lowell, necessitating season-ending surgery.

He returned in 2019 and got off to a slow start at Low-A Greenville before taking flight. Hitting just .208 through April with 31 strikeouts and only two homers in 22 games, Casas hit. 267 with 18 homers and an .870 OPS thereafter, striking out a more manageable 87 times in 98 games.

"Once you get in that 450-500 at-bat level of the season, it starts to get a little comfortable," Casas said. "I felt like I was having my best at-bats in August, and when the season ended, I was a little disappointed that we didn't have another month left. I'm looking to build on that momentum and bring it into the season."

Casas finished third in the South Atlantic League with 19 homers (he added his 20th during a September cameo with High-A Salem), and no other teenager cracked the top 10. He joined Xander Bogaerts and Tony Conigliaro as the only Red Sox teenagers to hit 20 homers at any level since 1960.

All of that slugging made him the unanimous No. 1 prospect in the organization, with his smooth left-handed swing drawing comparisons to Braves All-Star Freddie Freeman.

"I'm more on the side of ignoring all of it," Casas said of the plaudits. "I try to live with the satisfaction that I'm happy with myself, and the numbers I'm putting up are a product of the work I'm putting in. I feel like there are a lot of improvements that need to be done, because I don't feel like I had my best season."

He was lucky enough to grow up near Padres first baseman Eric Hosmer, a fellow graduate of Heritage High School. Hosmer has served as a mentor for years, though Casas likes the idea of closing the student-teacher gap as he gets closer to the big leagues himself.

"I've talked to him a couple of times this offseason, a little more often now that I've signed, just because we have a little bit more compatibility and we're a little more relatable to each other," Casas said. "He's a really good mentor. He's kind of like the first big leaguer I've ever talked to, growing up, he's in the area and I don't know if he's always felt the need to take me under his wing, but same high school, same area, he's been really beneficial to my career."

If there's a player Casas admires, it's Reds first baseman Joey Votto. Despite his natural power, Casas chokes up like Votto, especially with two strikes, "where I'm way up on the pine tar."

"I emulate Joey Votto as much as I can," Casas said. "He's my favorite player."

He won't be Votto until he limits the strikeouts. He ruefully noted that he recorded more K's (116) than hits (107) in 2019.

 

"That was a very concerning stat for me," he said. "That's something I got back in the cage and focused on. I feel like it has a lot to do with your mentality stepping into the box, being ready to hit right from the first pitch. But it's something that I learned from last year. Last year was a big learning experience, so I'll look to build on it this year."

Casas hopes to build, and maybe he'll continue to grow, too. Whatever happens, he knows this much: he's not in the game simply to be a highly regarded prospect.

"To be recognized by a lot of people as the Red Sox' best minor-league player or hitter, it's really nice," he said. "But at the end of the day, I don't want to be a minor league player."