Zack Greinke Traded from Diamondbacks to Astros for 4 Prospects at Deadline

The Houston Astros announced they have traded for six-time All-Star starting pitcher Zack Greinke from the Arizona Diamondbacks.

According to ESPN's Jeff Passan, four minor league prospects are going to Arizona: starting pitchers Corbin Martin and J.B. Bukauskas, first baseman/outfielder Seth Beer and utility man Josh Rojas. MLB.com's Mark Feinsand noted that Kyle Tucker is not part of the trade. Tucker is 13th on MLB.com's list of the top 100 prospects.

The Diamondbacks are sending $24 million to the Astros while Houston will absorb the remaining $53 million of Greinke's contract, per Ken Rosenthal of the Athletic. 

Greinke has been excellent to start the 2019 season. Through 22 starts, he's 10-4 with a 2.87 ERA and a 3.15 FIP. He's also averaging 8.17 strikeouts and 1.15 walks.

The right-hander has improved following a 2018 campaign in which he was solid but not otherworldly. 

Greinke was 24th among pitchers in WAR (2.9). He had a 3.71 FIP and averaged 8.62 strikeouts. His step backward came despite opposing hitters batting .272 on balls in play, the third-lowest BABIP of his career.

If they thought they could push for a deep playoff run, the Diamondbacks almost certainly would've kept Greinke for the remainder of 2019. At 54-54, Arizona is 15.5 games back of the first-place Los Angeles Dodgers and three games off the final wild-card spot.

However, this move signals the franchise's shifting priorities.

The teardown began this offseason. A.J. Pollock and Patrick Corbin left as free agents and the Diamondbacks traded Paul Goldschmidt to the St. Louis Cardinals as he entered the final year of his contract. The Cardinals subsequently gave Goldschmidt a five-year, $130 million extension following the trade.

Arizona went from having the 14th-highest payroll ($143.3 million) in 2018 to the 17th-highest ($124.9 million) in 2019. Considering he was the team's biggest earner, trading Greinke was the next logical step in the Diamondbacks' cost-cutting process. 

For the Astros, the addition of Greinke solidifies the rotation midway through a 2019 season with high expectations.

The window has probably closed on Greinke winning a second Cy Young Award or enjoying a year like he had in 2015 (2.76 FIP and 5.4 WAR). He turns 36 in October and has logged the third-most innings (2804.1) of any pitcher since 2004.

His fastball velocity has declined in each of the past four seasons as well, averaging 90 mph in 2018, per Brooks Baseball.

The fact that Greinke doesn't rely on overpowering stuff may prolong his time as a top-three starter, though. He can still use a variety of off-speed pitches to keep hitters on their toes, just not with the same strikeout rate he could manage during his prime.

Perhaps Greinke's production falls off a cliff in the second half of 2019 and into 2020, but nothing in his past performance indicates that will be the case. He should continue to be an effective presence on the mound, which is exactly what Houston needed to bolster its roster.

Plus, the Astros have the pitching depth to withstand any minor decline from Greinke. He's going from the clear No. 1 starter in Arizona to likely being third in Houston's rotation behind Justin Verlander and Gerrit Cole.

Stats are courtesy of FanGraphs unless otherwise noted.