The Winding Road to a Normal Carlos Gonzalez Season

For those casual baseball fans who might have found residence under a slab of basalt for the past two months, let’s get you up to speed: Carlos Gonzalez has been locked-in recently. Post All-Star break (that date chosen for simple convenience), CarGo is fourth in baseball in wRC+, tied for first in homers, and first in ISO. So, on Monday night, we shouldn’t have been too surprised when he did this:

Seeing the initial flight of the ball while watching this game, I thought this was a double in the gap that was going to short-hop the fence. The Rockies telecast said about the same thing. Instead, it was a frozen rope that didn’t come down, sailing into the first few rows of bleachers.

Per Baseball Savant, it was the thir- hardest-hit home run by a left-handed hitter to the opposite field all year (110 mph) — and , considering it was only two mph slower off the bat than the hardest one (Pedro Alvarez, 112 mph), it’s right in the same territory. That’s not quite all: if we want to dig a little deeper, it was the hardest-hit ball by a left-handed hitter off of a left-handed pitcher all season. CarGo isn’t known for his ability to hit lefties, but this is a prime example of just how hard he’s hitting everything right now.

This all leads to the inevitable question: how did Gonzalez turn his season around? Eno addressed CarGo’s lack of success in mid-June, showing that the slugger’s batted-ball velocities were in line with a higher expected level of production than he was showing. He was getting a little unlucky on hard-hit balls, yes, but that might not have been the whole story. So what has happened in the past couple months?

There’s a simple, obvious component: he’s hitting the ball much harder. Take a look at his average exit velocity by week of the season, again from Baseball Savant:

Starting about two months ago, his average batted-ball exit velocity jumped to well above the league average and stayed there. That’s a simple solution for any struggling hitter: start hitting the ball hard consistently.

That’s not the whole story, though. He’s also changed his plate approach drastically from earlier in the year. Let’s look at his plate discipline numbers prior to June 1st vs. afterward:

	O-Swing%	Z-Swing%	Swing%	O-Contact%	Z-Contact%	Contact%	Zone%
Before June 1st	30.3%	70.5%	47.8%	54.8%	82.7%	72.7%	43.4%
After June 1st	40.0%	76.7%	56.0%	54.8%	83.2%	71.7%	43.7%

He’s now swinging more — a lot more. In the past two-and-a-half months, he’s been swinging at pitches both inside and outside of the strike zone at the highest rates of his career. This is one of those small sample size examples that could be driven by a positive feedback loop — swing more and get good results, which leads to swinging more often — but it is still a quite noticeable shift from earlier this year, when he was posting plate-discipline stats more akin to the earlier years of his career.

Another change has seen him couple a tendency to hit more fly balls while pulling the ball at a greater rate, a combination that can drive a surge in power numbers. Take a look at his batted-ball breakdown along with his pull tendency, again for the timeframe we’ve been looking at:

	LD%	GB%	FB%	HR/FB	Pull%
Before June 1st	23.0%	51.1%	25.9%	11.4%	38.2%
After June 1st	13.6%	42.0%	44.4%	29.3%	44.1%

Hitting the ball hard in the air to the pull side is a great way to go on a home-run tear, and it’s the big reason why Gonzalez has posted an absurd 29.3% HR/FB rate since June 1st. That’s obviously not a sustainable rate, but CarGo has posted a HR/FB rate above 20% in three of the past five years of his career (2010, 2011, and 2013), showing that this sort of territory is not unheard of from him.

So what changes did he make to start yielding these better results? One of them was to start covering the outside part of the plate. Let’s take a look at where in the zone CarGo has hit for power — comparing his pre-June 1st heatmap with one from after June 1st (courtesy of Brooks Baseball):

Interestingly, his power has dried up in the low and inside part of the zone, where he was most successful earlier in the year. However, he’s shown much better coverage over the outer part of the plate and down in the zone since June 1st. My first thought was that he had to have moved closer to the plate, but he hasn’t: he still stands in the far back corner of the box, and has for the entire season.

Maybe he’s extending his arms better to drive those pitches on the outside corner; maybe he’s made a different mechanical adjustment. What we do know is that this greater power in more parts of the zone is some combination of his increased aggression, better contact, and propensity to hit more fly balls.

Perhaps the most interesting thing about Carlos Gonzalez’ 2015 season is that it has been divided into two of the most disparate parts you will ever see. Prior to June 1st, he posted a 66 wRC+. He was getting a little unlucky, but he also looked terrible. Reports of his potential demise were featured on these digital pages. After June 1st, he’s posted a 166 wRC+. He’s feasting on any and all pitching, hitting dingers with abandon, and he looks like the CarGo of old — except without the speed.

That final part of his game might never come back. We might now be seeing the post-prime Gonzalez: a 25-30 home-run threat with average patience, average-ish defense, and almost no speed on the base paths. That’s still a very valuable player, but it’s not the healthy glimmer of a five-tool guy that we have seen over the past few years. CarGo looked done in the first two months of the season; then he roared back all at once by being more aggressive, hitting a ton of fly balls, and pulling the ball more. Unfortunately, April and May still count, and he now finds himself toward the end of a twisting journey whose destination is pretty familiar.