Growth spurts are pretty common for a high schooler, but for Brandon Barriera, they were as much mental as they were physical.

The 18-year-old left-handed starter, who was the Blue Jays’ first-round selection in the 2022 MLB Draft out of Florida, is admittedly a late bloomer.

“Growing up, I wasn’t the greatest pitcher on the circuit,” Barriera told reporters on Friday, from the Blue Jays’ Player Development Complex in Dunedin, Fla. “Things didn’t click for me until my freshman or sophomore year. That’s where I really started to see dramatic changes and started getting more confident with my stuff.”

The improvements didn’t happen in a vacuum. Nor were they the product of any drastic mechanical or physical enhancements.

What sparked the change, Barriera says, was his mentality.

“Getting into the groove of things. Getting into routines,” he said during his first media availability as a member of the Blue Jays. “Not only baseball-related, but off the field. Going to bed at certain times, trying to get as much rest as I can, eating three meals a day. Hold myself accountable in all these things.”

To sum it up, he gained some maturity.

Barriera, the No. 23 overall pick in the Draft, now has a prime opportunity to keep nourishing those acquired routines while focusing solely on baseball for the first time in his life. A product of American Heritage High School in Plantation, Fla., he has spent the last couple of weeks at the Blue Jays' Draft Camp in Dunedin. It’s given him the chance to meet other Toronto Draft picks and the coaching staff, as well as ease into all the moving parts of developing a potential elite-level Major League pitcher.

“It’s great to meet a bunch of these new players and just get their takes on how they go about things, learning from them,” said Barriera.

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From now until September, the 6-foot-2, 180-pound lefty will stick to light throwing, taking the opportunity to get acclimated to his new surroundings and the Blue Jays’ different player development departments -- from strength and conditioning to mental fitness.

That means Barriera will go five months without live pitching action, as he decided to shut down his senior season ahead of the high school playoffs to prevent injuries and prepare for the Draft. The decision seems to have paid off.

“Looking at the bigger picture,” Barriera said of his decision. “The best that I can do is be available. So, coming in here, I wanted to make sure that I was the best body-wise on the field and off the field.”

But that calculated choice hasn’t deterred his overtly intense competitive spirit. From disciplining himself into becoming a better pitcher to declaring on live television that the 22 teams that passed on him in the Draft would “regret” it, Barriera has always pitched like he’s got something to prove.

“I have this bulldog mentality where I go about things a different way,” he said. “When it comes to competing, I take that stuff real serious. It’s what I love to do, I love to play the game of baseball. I’m not going to let anyone take that away from me.”

That demeanor is part of what drew the Blue Jays to Barriera in the first place. Pair that with an advanced four-pitch mix and a fastball that has touched 98-99 mph, and the organization believes they’ve got something special.

They didn’t mind his decision to shut down early, either.

“It is a bit different and unique of a case,” Shane Farrell, Toronto's director of amateur scouting, told reporters on Friday. “But we made sure to do our homework on him and get to know him as a person, not just the athlete, and ultimately felt really comfortable with our decision.”

Come September, when Barriera starts throwing live BPs from the Player Development Complex, the Blue Jays will get a better idea of where their first-round pick stands ahead of his arrival in the Minor Leagues. The scouting reports, however, have been complimentary of the fastball and slider, his main secondary pitch. Barriera has also developed a good curveball and continues to work on a changeup that would round out an attractive four-pitch repertoire in the long term.

He's ready to put in the work.

“In baseball, your talents can only take you so far,” said Barriera. “It’s all about your mentality and how you keep yourself composed. Because baseball is probably one of the hardest sports -- if not the hardest sport -- there is.”