Miguel Castro has the “stuff” of a lockdown bullpen arm. He can reach back and get an upper-90s fastball on occasion, and offers up good enough secondary pitches to keep hitters honest. But he has now spent two years with the Orioles, and we are still waiting for everything to click together for the 23-year-old.
Many of Castro’s stats slipped this season from where they were in 2017. His ERA went from 3.53 to 3.96. His ERA+ fell from 123 to 105. His FIP is up from 4.94 to 5.11. Many of those struggles, however, can be traced back to a horrific month of August, where he accumulated a 9.75 ERA in 12 innings over 11 outings. Castro allowed 10 home runs all year; five of them came in August.
The peripheral numbers don’t look great for Castro this year either. He did strike out more hitters this year, but for a guy with a big fastball he should be averaging more than 5.94 K’s per nine innings. He was extremely wild, walking 5.21 hitters per nine innings as well. Part of the problem was that fewer hitters (25.8 percent) were chasing his pitches out of the strike zone.
Despite the troubles, the lanky right-hander was still one of former manager Buck Showalter’s favorite relief options throughout the 2018 season. His 62 appearances were second on the team behind Mychal Givens (69). But Castro’s 83.2 innings blew all of his fellow Orioles bullpen mates out of the water. In fact, that was the fourth-most innings thrown by one reliever in the entire league.
That number of innings may have been a bit extreme for Castro, especially with Showalter bouncing him back and forth between responsibilities. Some days he was a crucial late inning arm. Other days he served in a long man capacity. He even made a spot start in the middle of the season. It was obvious that the coaching staff thought highly of him, and wanted him to have a key position in the bullpen, but that role was never clearly defined.
There is some evidence to suggest that Castro could be a crucial piece of an Orioles staff that takes a crack at the “opener” craze. He has the ability to go more than one inning at a time. His sweet spot for rest was three days. As a reliever, he allowed just three runs over 16 innings this year when given three days in between outings. And Castro did perform better against right-handed batters (.230/.338/.332), but the splits against lefties (.244/.357/.420) are not bad enough to keep him away from them altogether. It could make sense to start him for two or three innings against right-handed heavy lineups.
None of this matters if Castro can’t utilize his fastball properly. It’s the pitch that lights up the scoreboard, but opposing hitters aren’t scared of it. They whiffed on it just 8.37 percent of the time, compared to 14.41 percent on his change up and 12.60 percent on his slider. As a result, it was getting crushed to the tune of a .460 slugging percentage.
The problem is not that he uses the four-seam fastball too much; it makes up just 58.16 percent of his pitches. Any pitcher worth their salt needs to establish a fastball in order to make any of their other pitches effective. But he needs to get more movement from the offering. According to Brooks Baseball, Castro’s fastball moved less this year than in any previous stint in the big leagues. That is why fewer hitters are chasing it out of the zone and why fewer hitters are missing when they swing at it.
The Orioles are almost sure to bring in a new coaching staff when they (eventually) hire a new manager. Castro could become the pitching coach’s new best friend. A slightly altered grip or the re-introduction of a sinker or two-seamer could make a world of difference for Castro. He needs to add to his toolbox if he is going to perform up to his potential.
Something to watch regarding Castro during the offseason and into spring training will be the condition of his knees. He had trouble with them last February, and then more swelling forced him to end his season about 10 days early back in September. A healthy off-season is always important, but even more so for a member of the Orioles that is expected to be a major contributor in 2019 and beyond.
What the organization does with Givens this winter also directly affects Castro. This is a bullpen with very little proven major league ability beyond Givens, Castro and Richard Bleier. If Givens is traded by the new regime, that could make Castro into the O’s go-to high leverage arm, which is a role that he may not be ready to take on.
A lot of questions remain about Castro, but hopes should still be high that he can develop into the club’s latest reliable reliever. He will be just 24 years old when the Orioles open the 2019 season. There’s time to improve his arsenal and correct his problems, but other talented arms are coming up through the system, and they will need to get their shot as well. The 2019 season will be Castro’s best chance to showcase his abilities and make a case to the league that Baltimore can still churn out nasty relievers.