PHOENIX -- Five starts into the 2016 season, Zack Greinke had a 6.16 ERA and the D-backs right-hander was not sure why.
"I thought I was doing all right, but the results were really bad," Greinke told MLB.com. "I didn't think I was pitching that bad at the beginning to have the results that I was getting."
That prompted Greinke to check out the numbers behind the numbers. Things like exit velocity and other advanced metrics, which can be found easily now, thanks to Statcast™.
What Greinke saw was that his exit velocity was still good, but his command was just off a bit.
"It made me feel better about what I was doing the first month," he said.
So Greinke didn't make any radical changes, and over his next 12 starts, he had an ERA of 2.63. Included in that stretch was a six-start winning streak during which he had a 1.60 ERA.
Greinke doesn't always pore over the numbers. If things are going well, he tends to not overanalyze things, but when he has some struggles, he will dig into the numbers to try and understand why.
Statcast™ helps explain why Greinke is having more success this year, and one of the biggest reasons has been the effectiveness of his slider.
Last year, the average exit velocity on his slider was 87.6 mph, which ranked 58th out of 84 qualifying pitchers. This year, he is tied for the fourth-lowest at 82.7 mph.
Greinke nodded when shown those numbers because it synced up with what he was feeling.
"This year, I've been throwing more sliders in the strike zone and on the corners," Greinke said. "I just know I've been attacking more with the slider close to the zone. This year it's been good even when it's in the zone, so I'm more comfortable in that spot. When the results are good, I'm going to keep doing what's working."
Since he is not a pitcher who relies on an overpowering fastballs, hitting the corners is an important element for Greinke to have success.
Last year, according to Statcast™, Greinke hit the corners of the strike zone with 8.7 percent of his pitches, which ranked 30th. This year he has hit the corners with 10.4 percent of his pitches, which ranks second.
That came as a little bit of a surprise to when he was shown the numbers.
"I feel like I'm doing a pretty good job of it," he said about hitting the corners this year. "The numbers say I'm doing better. Most of the time I felt like I could do that last year, but looking at it I wasn't."