Castellanos, 27, has been a consistent force on the offensive side of things over the last few years and 2019 was one of his best seasons yet.
The outfielder hit .289/.337/.525 with 27 home runs and 73 RBI in 151 games split between the Detroit Tigers and Chicago Cubs. That gave him a 121 wRC+ and 2.8 fWAR according to FanGraphs.
His defense is what brought his fWAR down as a bat of that caliber usually results in the player being deemed as more valuable than that.
In 2019, Castellanos had a -4.4 UZR and -9 DRS in right field over the course of 1,171 innings. In left field, he had a -0.8 UZR and 0 DRS over a very small sample size of 35 innings.
While those numbers still acknowledge that Castellanos’ defense is poor, to say the least, it was actually a very significant improvement from his 2018 defensive metrics.
His -12.9 UZR and -19 DRS in 2018 was virtually unbearable in right field and made many question if he was a DH being forced into playing the field.
In 2017, he showed even less promise in right field with -7 DRS and a -7.7 UZR in a mere 173 innings.
So, the point of this is that he has actually shown significant improvement defensively in each season since that abysmal start to his outfield career.
Now, I am not saying that his bad defense should be assumed to improve every year. The fact is that most players lose range over time instead of gaining it.
That being said, one of the things working in Castellanos’ favor this offseason is that he is a free agent at the age of 27 and as someone just entering their prime, there’s no reason to believe that he would actually fall backward speed and range wise yet.
It should also be noted that taking a gamble on someone like Castellanos improving defensively wouldn’t compromise the team too much if he doesn’t.
A National League team has much more to worry about when it comes to signing Castellanos as they don’t have a DH spot as a fallback option. That is why the Chicago Cubs really need to consider the idea of re-signing him very carefully.
Nicholas Castellanos’ defense certainly isn’t something to ignore if the White Sox try to sign him. But, with improvement being shown since his transition to the outfield in 2017, Castellanos is a worthwhile addition for the team.