Orioles reliever Miguel Castro is on pace to throw more innings in the second half of the season than any reliever over the past five years, and as the season winds down, it's becoming clear that the workload is starting to catch up with him.
It shouldn't be surprising, because the 85 innings Castro has thrown this season between the Orioles and Double-A Bowie are the most of his professional career, even going back to when he was a starter coming up through the Toronto Blue Jays system.
He's never experienced this kind of workload, and there hasn't been a reliever used more than Castro in the second half dating to 2013 other than the Houston Astros' Chris Devenski last season.
Devenski logged 44 2/3 innings after the break in 2016, and Castro entered Tuesday with his second-half innings total at 44 1/3 with 11 games to go, so he's likely to pass that.
The 24-year-old Castro has obviously been an important part of the Orioles bullpen, forming a middle-inning bridge while also serving as the team's top option for length in extra innings, as was the case in Monday's 10-8 11-inning loss to the Boston Red Sox at Camden Yards.
Of course, manager Buck Showalter would've liked to avoid using Castro on Monday. He also would've liked for the Orioles to hold on to an early lead, but that didn't happen.
As it sits now, Castro's 44 1/3 innings since the break are more than any other major league reliever — and by a lot. The Colorado Rockies' Chris Rusin entered Tuesday ranked second with 35 1/3 second-half innings.
"You have to have look at that," Showalter said of Castro's innings. "But that's something all guys fight this time of year. It's something we keep an eye on. He's another guy that [pitching coach] Roger [McDowell] and [bullpen coach] Alan [Mills] and I are on top of, and the trainers every day. Nobody works harder than him. He really wants this. But sometimes we have to be the voice of reason with guys like that because the want-to gets in the way of should you. But we look at it every day. We make sure we keep our arms around that."
Over his first 32 appearances this season, Castro had a 2.38 ERA, allowing just 38 hits and 16 walks over 53 innings. He allowed runs in just 10 of his first 32 outings.
But over his past five appearances, the right-hander has a 9.39 ERA, allowing six hits and 10 walks over 7 2/3 innings. He's allowed runs in each of his last five outings.
He's not necessarily allowing many more hits — his opposing batting average over those five outings is .222 compared to .205 before that — but his walks are up dramatically.
He has issued three walks in three of his past five outings, after having he had just two three-walk outings through his first 32 appearances.
"The thing that I notice is that sometimes I lower my arm angle too low, and that gets me in trouble, but that's just an opportunity to improve and get better and work at it," Castro said through interpreter Ramón Alarcón when asked about the recent surge in walks.
On Monday, Castro breezed through his first inning, in the 10th, retiring the Red Sox in order, including strikeouts of Mookie Betts and Rajai Davis, both looking at 98 mph sinkers.
But in the 11th, he walked the bases loaded with two outs — leaning more on his changeup throughout the inning — and then threw four straight changeups to Andrew Benintendi, before a 2-2 sinker that landed in right field for a two-run single that would decide the game.
"He's struggling a little bit to finish off good at-bats," Showalter said. "He'll get ahead and then let the hitter get back in the count. He's had a lot of situations where the command of the fastball, he put somebody away after the changeup or the breaking ball. And he did that some. … After throwing an inning and a third, he was fine physically. The command to finish off some at-bats, you see some of the counts get in his favor. We've been challenged with that a lot, with putting guys away. We go from 0-2, 1-2 to 3-2 in a hurry."
But Castro insists fatigue isn't a problem.
"I'm ready to go," he said. "This is my job. I'm available whenever I'm called, so I'm ready to go."
Castro is probably the Orioles' top uncovered gem of the season, acquired from the Rockies in April for a player to be named that was later determined to be minor league right-hander Jon Keller.
The club recognized Castro was fast-tracked too quickly by the Blue Jays and sent him to Double-A for seasoning, then made him a valuable piece of the bullpen that the team lacked through the middle part of the season.
Some believe he could be a major league starter — he was groomed as such in the minors before Toronto fast-tracked him to be a power reliever — and he could be in the Orioles' major league rotation as soon as next year.
But first the Orioles have to get him to that point, because with their need for pitching — whether it's in the bullpen or rotation – they have to protect their assets.