Well, that didn’t take long. Less than 48 hours after the non-tendering of Steven Souza reduced the count of functional outfielders on Arizona’s 40-man roster to three, we get the first of what’s likely to be many rumors linking the D-backs to a free-agent replacement. Getting the ball rolling was Jon Morosi of MLB Network, who Tweeted:
Morosi had previously reported that the Giants and Cubs were also among the suitors for Castellanos‘s services. On the surface, this seems like a potentially interesting fit. He has hit at least 23 home-runs in each of the past three seasons, mostly with the Tigers before a trade-deadline deadline deal to the Cubs this year. Over 2017-19, his triple-slash line is .287/.337/.405 for an .842 OPS and an OPS+ of 120. He is still only 27 years old, so it’s not like he should be falling off the aging cliff in the near-future. He has also been very durable, averaging 155 games per season during that time-frame. You can see why MLB Trade Rumors project him to get a four-year deal, worth $58 million.
But this does not come without a big red flag, in the shape of Castellanos‘s defense, which is terrible at a near-epic level. In those same three seasons, Baseball Reference rates him at 49 runs BELOW average. He’s basically battling with Xander Bogaerts (-51) for the title of worst defender in baseball over that period, with a big drop-off to the third-worst Melky Cabrera at -42. That has gone a long way to counter-balancing his value with the bat, and is why Castellanos has totaled only 6.5 bWAR from 2017-19. For an average annual value of $15 million per year, that’s... okay. But worth remembering that, dragged down by the everyday anchor of his defense, Nick doesn’t have a three-win season in his career to date.
However, MLB.com’s Mike Petriello points out the player was considerably better in 2019, largely by improving on the relatively easy plays. “In 2018, Castellanos failed to collect 17 plays that had a Catch Probability of 80% or higher... In 2019, he cut that number in half, to just 9 of those highly damaging misplays.” Also worth remembering, he only started playing significant amounts of outfield in 2018, having been almost exclusively a third-baseman to that point in the majors, after being drafted as a shortstop. He still has less than the equivalent of 500 pro games in the outfield; embarrassing plays like the one above will happen to novices. Just ask David Peralta - now reigning Gold Glove champion in left-field.
I’m still fairly skeptical the Diamondbacks would be interested in Castellanos. It’s clear the team will be acquiring another outfielder, so can safely be said to be “in the market” for almost anyone, and I’d be expecting them to do their due diligence on any and all available options. That said, of the big three outfield names on the free-agent board this year - Castellanos, Yasiel Puig and Marcell Ozuna - Castellanos is the youngest and perhaps would make the most sense for the Diamondbacks.