Between Miller and Segura, did the Diamondbacks trade too much?

Between the Shelby Miller and Jean Segura trades, the Diamondbacks have given up their two best prospects in Dansby Swanson and Aaron Blair, a .300 hitter in Ender Inciarte, a former second-round pick in Isan Diaz, and a rotation fixture in Chase Anderson. Throw in the 13th overall pick they forfeited to sign Zack Greinke, and their offseason has racked up quite the tab.

There is no question that these trades have made the 2016 Diamondbacks a better team. Miller makes the team’s rotation arguably the National League’s best outside of Queens, New York. Segura has a star-caliber upside. Arizona now has one of the National League’s best on-paper rosters—which is astounding considering they lost 99 games in 2014.

It’s always tough to pick the winners and losers of a trade where players have yet to take the field for their new teams. In reality, only time will tell. But on the surface, the only way the Diamondbacks will be able to justify the price they paid in these trades—and on the Greinke deal—is with immediate results and championship-caliber baseball over the next three seasons.

After 2018, Paul Goldschmidt, A.J. Pollock, Patrick Corbin, Miller and Segura will become free agents and Zack Greinke will be 35. So this team realistically has three years to make a serious run at a World Series championship.

If a World Series is bought to Arizona and Dansby Swanson, Ender Inciarte and Isan Diaz all become Hall of Famers, the trades still would be justified because they bought the team to the pinnacle. But if Arizona disappoints—as the Padres did after their grandiose offseason last year—these trades could go down amongst the worst of all time.

Looking at each player’s pedigree, it looks like Arizona may have spent a little more than either was worth. Both Miller and Segura have tremendous upsides, but neither of them is an elite player. It’s true that Miller posts a lifetime ERA of 3.22, but his 3.82 FIP indicates he may – to some degree—benefit from good luck. His 3.77 ERA over his final 23 starts last season was also quite pedestrian.

The price tag on Miller was considerably expensive. MLB Pipeline ranked Swanson as the tenth-best prospect in all of baseball and Blair as the 61st-best. Inciarte is just 25 and already has a .300 season under his belt. The Braves always seem to know what they’re doing in respect to their farm system, and have a two-decade long track record of solid long-term planning. There may be a reason they did not see Miller as a long-term fit.

In the case of Segura—unlike the case of Miller—the Diamondbacks seem to have been trading on the presumption of potential rather than the presumption of track record. Segura was once the Angels’ best prospect not named Mike Trout, and was the centerpiece in the trade that bought Zack Greinke from Milwaukee to Anaheim.

Segura has regressed after an All-Star 2013, batting just .252/.285/.331 while playing subpar defense since 2014. The Diamondbacks gave up Chase Anderson and underrated prospect Isan Diaz to acquire him.

Anderson’s numbers weren’t pretty, but pitchers who can throw 150 innings with five years of team control don’t grow on trees. Arizona also parted ways with shortstop Isan Diaz, a 2014 second-round pick who was the MVP of the rookie-level Pioneer League last season. Peter Gammons said that the 19-year-old Diaz was drawing comparisons to Robinson Cano in high school, while Yahoo Sports’ Jeff Passan said that “quite a few executives,” were high on Diaz.

Segura may have All-Star potential, but he has not reached that level in two years. This trade is going to be a gamble—entirely contingent on whether Segura can play like he did in 2013. If he can, then this is a steal for Arizona.

These trades will not hurt the Diamondbacks this season. They probably will not even hurt them next season. But in the not too distant future, this hemorrhaging of prospects will eventually catch up to them. The Diamondbacks have a three-year window to win a World Series. If they win one—or at least come close a few times—these trades will have been worth it. But if even one of these players becomes a star and the Diamondbacks fail to meet expectations, the team will face the consequences for years to come.