Why Zack Greinke Is Great for the Arizona Diamondbacks

The Diamondbacks shocked the world. The Dodgers are scrambling.

That's the effect of Zack Greinke's surprising decision to sign a six-year, $206 million with Arizona, a deal that will pay him an average annual salary between $31.5 and $32 million a year. The pickup is a coup for the Diamondbacks, who, as I wrote about last August, finished up the 2015 season with a ton of momentum, a playoff-caliber offense and defense, but shortcomings in the starting staff.

On Friday, they shored up one of those shortcomings in a big, big way. Last season, Greinke was a machine, going 19-3 with a 1.66 ERA, 2.76 Fielding Independent Pitching (FIP), and a bWAR of 9.3, highest of any pitcher in baseball. In 222 2/3 innings, Greinke allowed just a .185 opponents batting average and posted a minuscule WHIP of 0.84, striking out 23.7% of batters he faced, while walking just 4.7%.

In my opinion, he was the best pitcher in the National League last year, even though Jake Arrieta took home NL Cy Young honors. 

While the D-Backs are still looking for another starter to pair with Greinke at the top of the rotation, landing the long-haired former Dodger could mean the difference between finishing around .500 and making the playoffs. 

The offense is already playoff worthy. Their .264 batting average, .324 on-base percentage, and weighted on base average (wOBA) of .319 were all third-best in the National League last year. Their .414 slugging percentage was second-highest, and their 720 runs scored was also second in the NL, behind only the Colorado Rockies.

But not only can they hit the ball, they can also run and play defense. They finished with the second-most stolen bases in the National League last season (132), and their FanGraphs' Def number of 53.8 was third-best in the NL in 2015. As a team, their 71 Defensive Runs Saved (DRS) dwarfed the next-closest NL team, the Marlins, who had 37. By comparison, the Kansas City Royals, who most assume has the best defensive team in baseball, had 56 DRS, 14 fewer than Arizona.

They have Paul Goldschmidt, a perennial MVP candidate. They have center fielder A.J. Pollock, who finished with the fourth-best fWAR among National League players this year (6.6). They have rookie third baseman Jake Lamb, left fielder David Peralta (.893 OPS, 26 doubles, 10 triples, 17 homers in 517 PAs), catcher Welington Castillo (17 HRs in 303 PAs), and outfielder Ender Inciarte, who was worth 3.3 fWAR in 561 PAs last year.

But the rotation was a major issue last season. They finished 11th out of 15 NL teams in starters ERA (4.37) and opponent batting average allowed (.262), 12th in FIP (4.41), 13th in home runs allowed per nine innings (1.23 HR/9), and 10th in WHIP (1.35). Rubby De La Rosa, Chase Anderson, Jeremy Hellickson, Robbie Ray, Patrick Corbin, Josh Collmenter and others all failed to give Arizona much of an advantage on the hill.

So yeah, signing Greinke was kind of vital.

But what about the team that is losing him? The Dodgers miscalculated that they would be able to re-sign Greinke, apparently unwilling to go to a sixth year with their former right-hander. Instead, L.A. signed free agent starter Hisashi Iwakuma, who threw a no-hitter last year but was nowhere near what Greinke was for Los Angeles.

Greinke's deal with Arizona takes him through his age-37 season. Certainly not ideal. But the rumored length of Iwakuma's contract is three years, which would take him through his age-37 season as well.

Clearly, Greinke-to-Iwakuma is quite a drop-off, one that L.A. will be hard-pressed to fix, unless they're willing to unload their farm system of every prospect they covet for Miami's Jose Fernandez, which is highly unlikely.

There is no doubt that Arizona incurs some risk by signing a pitcher already in his early 30s to a deal that will pay him more than $30 million a season into his late-30s. But for a team without a lot of big contracts on the books, and an offense that is ready to make the postseason, the gamble is worth it for the Diamondbacks perhaps more than most teams.

For the Dodgers, worries they are wasting Clayton Kershaw's prime grow stronger.