TORONTO -- Vladimir Guerrero Jr.’s rookie season was a marriage of expectation and reality, but even with so much focus on the Blue Jays’ external additions this offseason, Guerrero’s Year 2 jump remains one of the biggest variables to the club’s 2020 success.

Held up as the game’s top prospect with a famous name that automatically brought more hype than a John Smith, it was Guerrero, not Houston’s Yordan Alvarez, whom fans expected to bash his way to the American League Rookie of the Year Award. That didn’t happen, with Guerrero's .772 OPS and 0.4 WAR (per FanGraphs) reminding us that while he is prodigiously talented, he’s still too young to buy a drink outside 29 of 30 Major League stadiums.

It’s difficult to overstate the importance of this offseason for Guerrero, as both he and the Blue Jays are focused on improving his habits now, not later. The jump between a first and second season can be challenging, with pitchers getting a better book on a young hitter, but Guerrero should only be a few adjustments away from the world-beating version of himself who made the Minor Leagues look like, well, a minor challenge.

“He’s been great. Everything he said he was going to do, he’s done and then some. He’s actually done more than we expected,” general manager Ross Atkins said in December. “He’s been with our staff members almost 75 percent of this offseason, other than the first roughly 15 days of the offseason, training in Dunedin.”

Guerrero’s body can be his greatest gift, but it’s also been a source of legitimate concern.

Vladdy’s workout plan

Guerrero is listed at 6-foot-2, 250 pounds -- a weight he entered 2019 Spring Training north of -- but to measure his overall fitness by one number is too simplistic an approach. While weight is undoubtedly a priority for all involved, Guerrero, like any other player, is also working on his flexibility, explosiveness and recovery habits, among other things.

This is more about ensuring that Guerrero feels strong on Sept. 30, and less about ensuring that Guerrero hits a number on a scale in February. Guerrero feels that he ran out of gas down the stretch as a rookie, which is natural for a player competing through September for the first time as a pro, so the end goal here is sustainability.

“My entire body, I feel a big change,” Guerrero said. “I feel lighter. I will continue with that. There’s still one month to go until Spring Training, so I’m not done yet.”

The Blue Jays eased Guerrero in with scheduled off-days in the Major Leagues, something they noticeably did not do with shortstop Bo Bichette. This won’t flirt with the NBA’s “load management” trend, but scheduled rest and the increased potential of DH days will all be part of the plan.

Manager Charlie Montoyo likes what he’s seen, too, and expressed his pride in Guerrero’s work this winter. This will be one of the top storylines of the spring, with every camera angle of Guerrero being dissected, and the extent to which he improves his body will directly impact the other areas he’ll need to improve in.

Hitting those angles

Guerrero’s sprint speed puts him in the 37th percentile of MLB runners, according to Statcast. That isn’t remotely concerning when Guerrero is driving the ball -- in fact, he can be surprisingly quick when the locomotive gets rolling -- but it’s problematic when Guerrero is hitting the ball on the ground.

Last season, Statcast measured Guerrero’s average launch angle at 6.7 degrees. Of the 406 MLB hitters who made at least 100 plate appearances in 2019, Guerrero's launch angle tied for 369th. It’s possible to have too much launch angle, like Guerrero’s new teammate Travis Shaw, who led baseball at 24.4 degrees in a very poor season, but 6.7 degrees isn’t going to work.

Guerrero should have no problem barreling up balls and creating monstrous exit-velocity numbers once he’s driving the ball in the air more often. In the Minors, one executive joked that the young slugger might hit more balls through the wall than over it. It’s an adjustment that is not just preferable, but necessary for Guerrero’s career, and a stronger physical base should help him create a more consistent swing to achieve that.

The corner is hot

The bar for Guerrero’s defense is not Gold Glove Awards, but his overall value would be much steadier if he can provide the Blue Jays with an average glove at the hot corner, even if it’s just for a few more seasons.

Using Statcast’s new Infield Outs Above Average (OAA) metric, Guerrero was worth -16 OAA in 2019, ranking last out of 218 qualified infielders. These numbers support the eye test in a more specific way, too, with Guerrero being worth -10 OAA on balls that he had to move toward home plate to field.

There is a real threat that more teams will challenge Guerrero with bunts down the third-base line, where he hasn’t looked natural or comfortable bending to scoop balls that he’s racing in on. While first base is likely Guerrero’s long-term home, the Blue Jays will be a better and more flexible team if Guerrero can take the next step defensively, where he certainly has the natural hands and short-area quickness as building blocks.