Jae C. Hong/AP
Long thought of as baseball's stodgy establishment, the New York Yankees have employed some cutting-edge tactics this season.
With a team ERA of 3.89, the sixth-lowest in MLB, New York has a solid cast of pitchers, but that doesn't mean they've adhered to baseball tradition. Despite having the highest average velocity in the league, Yankee hurlers throw the fewest fastballs of any staff - a paradoxical distinction in a season that's been full of surprises.
Conventional wisdom has long dictated that a pitcher must establish his fastball and work from there. Twenty years ago, a fastball rate of less than 50 percent would have been unthinkable. Even two years ago, there wasn't a team in baseball that threw heat less than half of the time.
But now? The Yankees have a fastball rate of 40.7 percent, completely ignoring any perceived threshold. Four other teams - the Rays, Indians, Astros and Angels, all playoff contenders - also possess historically low rates, meaning that a heavier reliance on off-speed pitches could be the next big trend in baseball.
Yankees pitching coach Larry Rothschild believes that heavy fastball usage is an inefficient strategy for dealing with today's hitters.
"Fastballs get hit," he said, according to Tom Verducci of Sports Illustrated. "It's amazing to me to see guys throwing in the upper 90s and they get hit. I don't know how these guys do it. That's how good major league hitters are. They have adjusted to velocity. To hit upper 90s you have to gear up for upper 90s. So hitters are going up there to gear up for velocity. And when they do that, they can hit it no matter how hard you throw."
Instead of inundating opposing batters with fastballs, the Yankees have the highest slider rate in the league: more than 25 percent of their pitches. According to Statcast, the league has hit just .218 on sliders this year, compared to .274 on fastballs.
The Mets, meanwhile, are tied for the fifth-highest fastball rate in the league but rank 28th in ERA. No matter how strategy evolves from here, it seems clear that establishing the fastball isn't necessary for success.
The Yankees pitching staff has greatly exceeded expectations this year. Two of New York's starting pitchers, Luis Severino and Jordan Montgomery, have never pitched a full season in the majors, while another one, CC Sabathia, is nearly 37 years old with a lengthy injury history. The bullpen has also come up big, with Adam Warren, Chasen Shreve and Chad Green performing just as well as marquee names Aroldis Chapman and Dellin Betances.