When Vlad Guerrero Jr. was in the minor leagues, scouts believed he had the potential to be one of the best hitters in the game. This was due, in part, to his power. Last season, Guerrero Jr. had a hard hit percentage of approximately 50%, and his average exit velocity was 92.5 mph.

But for someone with so much power, it comes as a bit of a surprise that his SLG so far is not as impressive. His SLG in 2019 and 2020 was .433 and .462 respectively. One explanation for the lower than expected SLG is that while he has the exit velocity to get barrels, he does not have the launch angle.

A barreled ball has a high exit velocity (98 mph+), a launch angle of approximately 25-45 degrees (varies), and typically results in a 1.500 SLG. Guerrero Jr.’s average launch angle in 2020 was only 4.6 degrees.

Looking at the graphic below from Baseball Savant, we see that a large number of Guerrero Jr.’s balls in play were outside of the barrel zone (bright red section). A large number of balls in play fall below the 0 degree line, which means they were hit even with the bat (line drive) or resulted in a ground ball.

This is backed up by Guerrero Jr.’s alarmingly high ground ball rate in 2020, at 55%.

Guerrero Jr. can be an incredible power hitter, but he needs to start hitting with a higher launch angle to start earning more extra base hits. One way to increase launch angle is to make mechanical adjustments.

Based on his limited spring training appearances, it looks like Guerrero Jr. is trying out a couple of mechanical changes this season.

What Mechanical Changes did he Make?

Two main changes stood out to me when comparing his pre-pitch stance:

• He is starting with a higher shoulder and arm position
• He is standing more straight up

This is something to keep an eye on for the first couple months of the season to see how his average launch angle and overall SLG are affected.

A Potential Added Benefit to the Swing Change

Another benefit of this change is that it can help Guerrero Jr. reach fastballs at the top of the zone. The heat map on the left below from Brooks Baseball shows his SLG is lower on hard pitches up in the zone. That’s backed up by the whiff % heat map below on the right, which shows he swings and misses at hard pitches up the zone most frequently.

If Guerrero Jr. increases his launch angle and is able to reach those pitches up in the zone, we are looking at a break out year for him. He has such great potential as a hitter and is a crucial a member of the offensive powerhouse that the Blue Jays are turning into. He is still a young player, and I believe he’ll be able to tap into all that power and start seeing results very soon.