Can Zack Greinke Replicate His Success in 2016?

After Zack Greinke finished second in Cy Young voting in 2015, the Los Angeles Dodgers seemed poised to give him the massive extension he was seeking. Continuing to pair him with Clayton Kershaw would give them an incredible one-two punch at the top of their rotation and make them World Series contenders for years.

The Arizona Diamondbacks had other plans.

By offering Greinke a sixth year that he wasn’t getting from the Dodgers, they were able to pry him away for the small fortune of $206 million. Greinke was one of baseball’s best pitchers this past season, but will the Diamondbacks be getting the same pitcher for their 2016 season?

Greinke posted the league’s best earned run average (ERA) at 1.66, the sixth best Fielder Independent Pitching (FIP) at 2.76, and the seventh best Wins Above Replacement (fWAR) at 5.9 in 2015, so expectations are high.

Let’s examine some of his stats from this past season to see if they are sustainable.

Does Past Success Equal Future Success?

His 23.7 Strikeout Percentage was slightly above his career average of 21.9 percent, and he’s had higher totals in past seasons, so there’s nothing that clearly supports he’ll strikeout fewer hitters in 2016. The same can be said for his Walk Percentage (BB%).

Despite posting the second best total of his career at just 4.7 percent, it’s not significantly lower than his career average of 5.9 percent. Greinke has always had above-average control, and has only surpassed a BB% of 7.1 once. Even if his walk percentage with Arizona increases to his career average, it would be better than league average and shouldn’t severely hamper Greinke’s ability to prevent runs from scoring.

Greinke was tremendous at limiting the long ball this season, as his 0.57 Home Runs per Nine Innings (HR/9) ranked fifth best and was the second lowest total of his career. While Greinke was superb at keeping the ball in the park, home runs allowed statistics have been proven to be mostly fluky from year-to-year, so it’s tough to say whether Greinke’s 2015 total is sustainable.

However, for pitchers who have thrown at least 1,500 innings since 2007 through 2015, Greinke ranks 14th in HR/9 at 0.84, meaning he’s managed to limit home runs for his entire career.

Area of Concern

One statistic that does stand out for Greinke is his Batting Average on Balls in Play (BABIP). His .229 BABIP was not only second best in baseball, but it was the lowest total of his career. In 12 seasons in the big leagues, Greinke has only had two other instances in which his BABIP was below .300. Considering Greinke’s career BABIP is .298, his total for 2015 appears to be an outlier. This suggests that a regression to the mean is coming and his BABIP can expect to creep back closer to .300, which, in theory, means he’ll allow more runs.

Perhaps one reason for his low BABIP is the percentage of fly balls he allowed. His 32.9 Fly Ball Percentage (FB%) was the highest it’s been since 2010. Fly balls tend to lead to a lower BABIP since the chances of them being caught are greater than ground balls or line drives that can sneak through the infield for hits. The increased fly ball rate, combined with a low Home Run to Fly Ball Ratio (7.3 percent), meant Greinke was able to limit the amount of runs he allowed.

Conversely, Greinke’s ground ball rate was the third highest of his career, with his top three totals all occurring in 2012 or later. He’s not allowing as many fly balls as he was earlier in his career and instead has become more of a ground ball pitcher. His Ground Ball Percentage (GB%) of 48 was significantly higher than his career total of 43.4 percent, which, despite potentially leading to a higher BABIP, is a good thing for run prevention. Ground balls are seldom turned into extra base hits, so in theory, inducing grounders means fewer runs allowed.

Greinke’s ground ball and fly ball totals were unique in 2015. His GB% ranked 29th best, and of the 28 pitchers ahead of him, none had a higher FB% than his. Understandably, a guy like Brett Anderson, who had baseball’s highest GB%, would not be able to come close to Greinke’s FB% because of his skewed GB%, but the important point for Greinke is that didn’t rely too heavily on either manner of contact allowed in order to get hitters out. His blend of grounders (read: not extra base hits) and fly balls (read: not home runs) helped lead to two things: fewer runs scored and a Line Drive Percentage of 19.1, the 16th best total this season. However, is it sustainable?

There’s nothing that suggests Greinke can’t replicate his GB% in Arizona -- it was actually higher in 2014 than this past season -- so it doesn’t appear to be a fluke. While his FB% was the highest since 2010, he broke 30 percent two other times from 2011 to 2014. Even if his FB% goes down, it shouldn’t negatively affect his ERA in a significant way.

Look at his 2014 season, in which his FB% was almost 4.5 points lower. He posted a 2.71 ERA that season, and while it is more than a point higher than his 1.66 this past season, only 12 pitchers had an ERA of sub-3.00 in 2015, meaning Greinke would still be in good company.

So it’s been established that Greinke isn’t showing signs of slowing down, but how does pitching in a new stadium and with a new defense behind him affect things?

His New Club

At first glance, the move appears to hurt his value. According to ESPN’s Park Factors, Dodger Stadium ranked 23rd in runs allowed per game at 0.918, while Chase Field (the Diamondbacks’ home) ranked 8th at 1.062.

However, fewer home runs were hit there, as Chase Field ranked 24th in home run Park Factor (0.856), whereas Dodger Stadium ranked 16th at 1.000. Greinke has proven his ability to limit the long ball, so this should play into his hands. OK, so what about his new defense?

Greinke had the best Left on Base Percentage among starters last season at 86.5 percent. Perhaps it’s due to bearing down with runners on, but let’s look at the defense behind him for a better sense of why his total was so high. The Dodgers had a solid unit last season, posting the 9th highest team defensive number according to FanGraphs at 33.5, although their Defensive Runs Saved (DRS) ranked 17th at -2, and their team Ultimate Zone Rating (UZR) ranked tied for 16th at 1.0. This suggests that they weren’t routinely bailing Greinke out.

FanGraphs’ Defensive number for the Diamondbacks was significantly higher at 53.8, which ranked third best, and they led all of baseball with 71 DRS in 2015. Their team UZR was also much higher at 23.8, which was third best. Greinke is getting a much better defense behind him, which could help make up for an almost inevitable regression in 2016.

The last factor to examine is Greinke’s repertoire. The percent of changeups he’s thrown has increased each of the last three seasons, leading to a career high of 20.9 percent this past season, and well above his previous career high of 16.5 percent, which occurred in 2014. Perhaps this helped lead to a career high percentage of strikes that were swung at and missed at 12.0 percent, also the 13th best mark in 2015. He’s relied less and less on his fastball since coming to the Dodgers and has posted three of the four lowest ERAs of his career. I imagine this trend of more changeups will continue in Arizona.

Another Cy Young Coming?

It’s all but a given that Greinke will not replicate his 1.66 ERA with the Diamondbacks, so while he’s due for a regression, his stats don’t suggest that a major one is coming. That, paired with playing for an improved defense behind him, make me believe that another Cy Young caliber season is in store for the 32-year-old.

As fellow numberFire contributor John Stolnis pointed out, all that was missing from the Diamondbacks' playoff push last season was a decent starting rotation. Now that they have Greinke and Shelby Miller, the Diamondbacks seem poised to knock off the Dodgers in the National League West.