Twenty-one homers, a career-high by seven. A .270 batting average. Only 118 strikeouts in 610 PAs. So, Starlin Castro is back on the map, right?
Not so fast. Castro did not just experience a sweet power-surge, as some may think. He greatly benefitted from an inflated HR/FB rate. Last year, his 15% rate was way higher than his previous career high (10.1%). Some may dismiss this stat and say that the move to Yankee Stadium helped him out, but in fact, the park factors on FanGraphs list Wrigley (106) as an easier venue for righties to hit homers than Yankee Stadium (105). As was often discussed amongst the Sabermetric community, last year the number of homers skyrocketed all around the MLB (possibly due to the balls being “juiced”), so take that with Castro’s inflated HR/FB rate and the most PAs he saw in a year since 2013, and we have a career-high in homers, even though Castro posted a fly ball rate lower than his career average and a popup rate higher than his career average. All of these homers helped lead to a career-high ISO, at .163. Because I don’t think the home run increase is sustainable, I don’t think the ISO increase is, either. He only hit 29 doubles, tying him for 51st out of the 88 players with at least 600 PAs last year. He also only hit one triple. Further undermining his ISO explosion, the league average ISO also ran up to its highest in ten years, fifth highest all-time, at .162. This was only the second time in Castro’s career that he had bested the league average ISO in a season (and he barely did so in 2016).
Accompanying this power surge was an erosion of plate discipline. Castro posted the second-worst walk rate of his career, at 3.9%. This was the third-lowest walk rate amongst the 88 hitters with at least 600 PAs last year. To make matters worse, his strikeout rate (19.3%) was the worst of his career. His swinging strike rate ballooned to 11.3%, way higher than his previous career-high (9%), and firmly below average. His chase rate was its worst since 2012, ranking 11th highest in the group of 88. If there is one good thing here, he also swung at pitches in the zone at the highest rate in his career. However, this could just be a function of Castro seeing a career-high number of strikes and him choosing to have a more aggressive approach (career-high overall swing rate as well, ranking 12th in the group of 88). Yet, he still made contact on pitches in the zone at the lowest rate in his career. Either way, Castro’s .300 OBP last year undermined his improvements in the power department, and he ended up with a below-average 94 wRC+. That OBP was the seventh-lowest amongst the 88 hitters with at least 600 PAs.
Noted for his speed as a prospect, Castro never actually posted a positive BsR (base-running runs above average) value in a season. His base stealing days appear to be over, as he only attempted to steal four times last year. Although he wasn’t caught once, he still posted a -1.6 BsR.
Did he at least hit the ball hard? Well, his Hard% was the second highest of his career, but it was still just below league average. His Soft% was a couple percentage points below league average, at least. His line drive rate was the second highest of his career (right around league average). But did his exit velocity improve? Of the 61 hitters with at least 400 batted ball events last year, Castro had the 43rd highest average exit velocity, at 89 MPH. The prior year, he ranked 44/55 amongst the hitters with at least 400 batted ball events, with an 86.5 average exit velocity. While Castro experienced quite a jump there, the average of the first group was 89.9 and the average of the second group was 88.9 MPH, so the entire league experienced a jump, and Castro ended up below average both years.
Starlin Castro is definitely a below average hitter. There are certainly some good things about him, but when he has a down year on defense, like last season, his offense isn’t enough to bank on–he only accumulated 1.1 fWAR in 151 games. This was the 11th worst amongst the 88 hitters with at least 600 PAs, and the worst amongst the second basemen in that group. Despite an uptick in homers, I don’t see enough of a skills improvement for Castro to maintain a 20-per season pace. I would expect something more along the lines of 15-per season, with his increased aggressiveness giving him more shots to lift the ball out of the park. This aggressiveness, however, can be his downfall: he doesn’t walk often and he doesn’t hit the ball hard, so some bad luck on balls in play could lead to a horrific OBP.
Data from FanGraphs and Baseball Savant. Graph made courtesy of https://nces.ed.gov/. Picture: USA TODAY NETWORK/USA TODAY NETWORK/SIPA USA–via nydailynews.com
Thanks for reading!