Javier Baez needs to change his swing, and the Cubs are working hard to accomplish that. When Baez first arrived in Mesa, he told Jesse Rogers with ESPN radio that the changes he plans to make are based on timing, but now it seems the Cubs are asking him to address specific swing mechanics.
I've gone in depth into the need for Baez to adjust his approach. But now that we know what exactly the Cubs coaching staff is asking him to target, we can go a little deeper into why the changes are needed.
Much of what Baez needs to work on mirror's another former Cub power hitter in Sammy Sosa. Before Jeff Pentland came aboard as the Cubs hitting Coach in 1997, Sosa had a very different looking stance. He held his hands high, causing more movement in his upper body in order to get into a proper hitting position. By keeping the hands up, the hitter's head will move down as he brings his hands down. This causes a change in eye level and sight lines as the ball is being delivered. Pentland convinced Sosa to bring his hands down to letter height.
While there is little doubt Sosa's breakout season in 1998 was helped greatly by is "Flintstone Vitamins", it's also when Sosa made changes to his stance and timing. And while there is no way to pinpoint when Sosa started taking his "vitamins", we can pinpoint a significant difference in his performance directly after the changes were made. One specific change the Cubs want Baez to make is his hands. They want his hands to come down and forward, just like whet Pentland did with Sosa. As you can see, Baez starts his hands in a similar position which in turn makes for a wildly moving upper body as he begins his swing.
As for the bottom half of the body, Sosa also went through massive changes and Baez will have to do the same. One of Sosa's biggest problems in his pre-1998 days was timing. Sosa was frequently ahead of fastballs and couldn't recognize breaking balls. By adding a hitch to Sosa's step, he was able to wait back better on off-speed offerings while staying behind fastballs. That hitch came in the form of a little step back with his front foot. As you can see in this 1993 at-bat against Greg Maddux, Sosa did not yet have that hitch.
And here is Sosa with his timing mechanism.
Baez has a different leg problem than Sosa. While Sammy had a minor leg kick before his changes, Baez has a heavily pronounced one. When this is added to the movement needed in his upper body, it creates a swing that is often out of control. The Cubs are asking Baez to cut down on that step, particularly on two strike counts. The idea being that a solid base will limit movement and allow him to wait back, similar to what the extra hitch did for Sosa.
These changes will not be easy for a 22-year-old who tends to get over excited during games. That rush of adrenaline may result in reverting to what feels natural. And one of the hardest changes to make in the batter’s box is to divert from what feels right.
Baez is very young and will have a lot of growing pains as he adjusts to big league pitching. But adopting these changes may have monumental results. By being proactive, the Cubs are taking the right approach in not letting his bad habits stick around.