Zach Britton’s week began with good news, as an orthopaedic specialist found no elbow damage on an MRI of the Baltimore closer’s injured throwing arm on Monday. It got worse on Tuesday, though, as an "industry source" shared that Britton would miss the next 45 to 60 days due to his forearm strain, leaving Baltimore hoping that he will return by the All-Star break in July. The team has not confirmed the report, but if Britton misses that much time in addition to the three weeks he has already spent on the disabled list, his absence could both harm the Orioles’ budding postseason chances and cast dark and unwelcome questions about the future of his closing career.
Any team would suffer from the loss of its best reliever, and Britton isn’t just any closer. The sinkerballer received notable Cy Young consideration last season and earned MVP votes after a campaign in which he didn’t blow a save and led all pitchers in win probability added; Mike Trout was the only position player to add more wins to his team’s ledger by that metric. As ESPN’s Sam Miller examined before the season, the Orioles in recent years have outperformed their preseason projections due to a consistently clutch and dominant bullpen.
Through five weeks, the 2017 season has seen much of the same: The 21–10 Orioles own MLB’s second-best record, but no team has outperformed its run differential by a greater amount this season, as Baltimore already has four more wins than its plus-13 differential would predict. The Orioles are 7–1 in one-run games and 4–1 in extra-inning contests — with some of those wins coming with Britton on the DL when his forearm troubles first flared up in April.
But an extended absence could stress Buck Showalter’s reserves to their breaking point. As with many injuries, this one isn’t so crushing because of Britton’s direct replacement: Brad Brach has a 2.12 ERA in 97.2 innings since the start of 2016 and still gives the Orioles one of the game’s best ninth-inning options. Rather, it hurts most because of the domino effect it inspires, with Baltimore’s lesser options being forced into the higher-profile innings subsequently vacated by Brach. Mychal Givens and Darren O’Day are capable of assuming those duties, but they struggle against opposite-handed hitters, and the names further down the line who are slated to take their places — the Alec Ashers and Logan Verretts of the pen — are more erratic still. (At least Ubaldo Jiménez is no longer relieving in tie games, after the wild-card disaster last October.)
Orioles starters rank 23rd in the majors in innings pitched per game, and Dylan Bundy and Chris Tillman are no paragons of health themselves. Baltimore’s bullpen is vital to its success, and losing depth in that area distorts the Orioles’ homers-and-bullpen strategy into a homers-and-hope-the-pitching-survives prayer.
Two months doesn’t necessarily spell disaster, though. Even assuming that Britton’s WPA from last year reflects his true talent — which it almost certainly does not, given how much that mark stood out as an outlier and how subject WPA calculations are to fluctuating context — he would be worth only two wins over a two-month span. By WAR, which is less kind to dominant relievers than WPA, he is worth only about half a win over a 60-day period. Baltimore can withstand that magnitude of loss.
More concerning is what Britton’s lingering arm troubles could mean for his career. He is an extreme ground ball pitcher: Since becoming a full-time reliever in 2014, he has run a 77 percent grounder rate, which is 10 percent higher than any other pitcher who’s thrown at least 100 innings in that span. Although the catalysts of pitcher arm injuries are still beyond the scope of current medical knowledge, the history of other extreme ground ball pitchers suggests that pitchers who rely on their sinkers might be more susceptible to severe arm problems. (Bill James thinks so, but the research is inconclusive.)
And even in Britton’s time on the mound this year, something seemed wrong. In April, his sinker’s speed was down a tick compared to the same point last year, and in his two appearances back in the majors this month from his first stint on the disabled list, he threw slower than he had in any game since May 2015. Britton’s maximum speed this month was still 1 mph lower than his average speed last year.
The history of dominant closers returning to peak form after suffering arm injuries isn’t encouraging, either. Greg Holland and Wade Davis are pitching well so far this year, but the stories of Eric Gagne and Brian Wilson are more representative — albeit involving more severe injuries than Britton’s diagnosis suggests — and, for Baltimore fans, frightening. Combine injured ground ball pitcher history with injured closer history, and the worry amplifies exponentially. As The Ringer’s Michael Baumann put it in Slack, "The list of top closers who missed significant time is much longer than the list of top closers who missed significant time and then returned to become top closers again."
Britton might not miss significant time, and he might return in July to continue adding to his consecutive-saves streak, which sits at an AL-record-tying 54; his elbow is fine, and Baltimore is playing great baseball at the moment. But Tuesday’s news sank those hopes, and the Orioles’ May and June suddenly look likely to be a whole lot worse than the April they just enjoyed.