When Vladimir Guerrero Jr. arrives in Dunedin, Fla., each spring, he tends to bring one of the biggest storylines of the offseason with him.

Coming into 2018 and 2019, Guerrero was the next big thing, the hopes of the organization resting squarely on his shoulders. In 2020, Guerrero’s fitness and position were in the spotlight, as he was moved to first base. This spring has carried over those same 2020 storylines, but in a more optimistic light for Guerrero, who turns 22 in March.

If you’ve checked Guerrero’s Instagram feed this winter, you’ve seen anywhere from one to one thousand clips of Guerrero working on his fitness, an issue that, to his credit, he’s improved significantly. With so much focus on that and Guerrero’s defense, though, as he campaigns to reclaim some of his reps back at third base, it’s taken the spotlight off his bat, which isn’t all that far removed from being considered a generational tool when Guerrero came up as the top prospect in baseball.

The Blue Jays expect Guerrero’s improved fitness to upgrade his production at the plate, but that’s a broad idea in a sport built on data and metrics. Let’s get a little more specific in terms of how, exactly, these changes translate to Guerrero being a better hitter.

“If you think about the reps that it takes and how many swings they'll take before they get into a batter's box to understand what's going to happen with a bat path at the right time to create the right trajectory of their swing, which creates the right trajectory on the ball, so much of it is about the athleticism that you can repeat,” general manager Ross Atkins explained Friday. “The better shape that you're in, the more repeatable things are going to be, because you're able to repeat them more in your practice.”

“Repeat” is the key word here. Late in 2019, Guerrero looked fatigued and admitted as much. There were still flashes of that violent swing, but too often, Guerrero’s hands and shoulders would drop, causing him to beat the ball into the ground. Looking at his metrics in 2019, Guerrero’s average launch angle of 6.7 degrees ranked him 369 out of 398 hitters with 100 or more plate appearances. In 2020, that number dipped even lower to 4.6 degrees, placing Guerrero 325 out of 352 hitters (50+ PA).

The idea, then, is that this improved version of Guerrero should be able to produce the best version of his swing more often. Maybe not 100 times out of 100, but at least more consistently than he has in the past couple of seasons.

Atkins also detailed the difficulty of evaluating hitters. It’s a chess game, and the pitcher always has the first move.

“It’s so dynamic and you don't know what the hitter is thinking, but you always know what a pitcher is thinking," Atkins said. "You always know what they were trying to do, and you know based on the outcome. You know where the catcher's set up, if he was trying to throw a fastball down and away or if he was trying to throw a backdoor slider. You always know, but with a hitter you don’t.”

This time last spring, hitting coach Guillermo Martinez noted that Guerrero searched for more power at the plate when he was fatigued, which caused him to “jump” at the baseball. By doing so, Guerrero lost some of the timing that made him a monster in the Minor Leagues.

When that happens, along with the hands and shoulders dropping, some of the power typically drawn from a hitter’s legs is lost, too. Even if you’re sitting in the back row of the 500 level at Rogers Centre, closer to the tip of the CN Tower than home plate, you’ll be able to see that Guerrero has big, strong legs. That’s where so much of his exceptional power lives.

In a perfect world for the Blue Jays, Guerrero’s offseason changes will help him to maximize his swing not just in camp, but throughout the course of 162 games and into the postseason. Exit velocity will never be an issue for Guerrero, but that launch angle, which can be solved by a fresh, consistent swing, is the key to unlocking the ceiling of his potential.

If Guerrero can repeat his athleticism, as Atkins put it, more often, that will free up some DH reps for the Blue Jays. Regardless of Guerrero’s split between first and third base, having him DH in over one-third of his games -- like he did in 2020 -- isn’t ideal.

“That was credit to Rowdy [Tellez], because we wanted Rowdy to play and he was swinging the bat well,” manager Charlie Montoyo said. “He earned his way into the lineup. This year, our lineup is pretty deep. I couldn’t tell you how many times Vladdy is going to DH, because the outfielders are going to have to DH, too.”

That last piece is important, as the Blue Jays essentially have four “starting” outfielders in George Springer, Lourdes Gurriel Jr., Teoscar Hernández and Randal Grichuk. If catcher Alejandro Kirk cracks the roster, that’s another bat worthy of the odd DH day, too. The Blue Jays are a better team if Guerrero is on the field every day, with the DH spot an option for others.

It’s still early days for Guerrero in 2021, but he’s done well with everything in his control up to this point. There’s no magic equation to translate these physical changes into batting average and OPS, but if they allow Guerrero to be his true self at the plate all season long, then this whole conversation will quickly shift back what got us started talking about Guerrero in 2015: his potential.