Everyone knows that strikeouts are up in baseball. Strikeouts are always up. In 2008, hitters around baseball struck out what was a then record 32,884 times. That seemed a pretty staggering number
The record has been broken every ... single ... year ... since.
It looked like we might be bumping against the ceiling there between 2014 and '15, when we saw an increase of just five strikeouts, from 37,441 to 37,446 ... but the past two seasons, we have seen strikeouts skyrocket again, up past 40K (40,104 in 2017). There are many theories about why strikeouts are up, and they usually have to do with hitters. But as the postseason begins, I want to focus on one thing about 2017 that seems undeniable:
Hitters are facing more dominant stuff than at any point in baseball history.
We'll see that ridiculous stuff on display the next two days in the Division Series. On Thursday, Boston's Chris Sale and Houston's Justin Verlander will face off in Game 1 of their American League Division Series presented by Doosan at Minute Maid Park. And then, for Friday's epic quadrupleheader, we'll get treated to the likes of Corey Kluber, Clayton Kershaw and Dallas Keuchel. Four of those five have won a Cy Young Award, and Sale could easily take one home this year. That's some serious stuff.
What does "stuff" even mean? There are various ways we can try to measure a pitcher's stuff. There is velocity, of course, and velocity looks to be up quite a bit since 2008. Across all pitches, velocity is up from 87.5 mph to 88.6 mph. Fastballs are up about 1 mph, too -- the top 25 percent of pitchers in 2008 clocked at 94.3 mph and that's now up to 95.3 mph.
According to advanced pitch tracking, pitchers are now throwing about twice as many pitches 98-plus mph as compared to 2008.
1. It seems pretty clear that, because of the more liberal use of power arms in the bullpen, velocity is up across baseball and ...
2. Velocity isn't the best way to measure stuff anyway.
You could also use spin rates or try to track how much the ball is breaking. But really, the best way to measure stuff comes from Hall of Famer George Brett, who says that if you want to see how well a pitcher is throwing, study how the hitter is responding. What kind of swings are hitters having? How bad do they look at the plate?
Great stuff forces hitters to do what? Right: Swing and miss. Right: Foul pitches off.
Hitters are doing those two things more than at any point in baseball history.

In 2008, hitters missed on 20.3 percent of their swings. That number has jumped to 24.3 percent. That's a big deal -- there were about 15,000 more swings and misses in 2017 than there were in '08. 
The foul-ball rate is not up nearly as much -- the percentage is only up about a half-point across baseball -- but it is 37.6 percent of all swings, and that's the highest rate of the past decade, making it almost certainly the highest rate in baseball history. Hitters are just having a hard time putting the ball in play. This, certainly, has to do with the incredible stuff starters and relievers having.
Now, you could certainly argue -- and there's data to support this -- that hitters are also swinging harder these days, going for broke more than ever before. But this doesn't change the fact that they are facing harder fastballs, nastier curves, more ferocious sliders and cutters and sinkers than hitters of previous generations. This pitching dominance -- and how hitters cope with it -- will probably be the decisive story of these playoffs.
Look at the Cleveland pitching staff, for instance. In 2017, the Indians did something that had never been done before -- no team had ever come particularly close to doing it before. They struck out 10 batters per nine innings. That's the ENTIRE PITCHING STAFF. As recently as 2006, no single starting pitcher in all of baseball struck out 10 batters per nine innings.

But this shows you the extraordinary stuff that hitters face these days. Clevland starters Kluber, Carlos Carrasco, Trevor Bauer, Mike Clevinger and Danny Salazarall averaged more than 10 strikeouts per nine innings. And then coming out of the bullpen, Cody Allen, Andrew Miller, Nicholas Goody, all of them came after hitters with overpowering stuff. Night after night, inning after inning, there were no breaks against Cleveland.
Houston's staff essentially did the same thing as Cleveland, averaging 9.9 strikeouts per nine innings. The Astros built their strikeout dominance more around their bullpen. You would expect Chris Devenski, Ken Giles and the rest to be a key force right away, beginning with the ALDS against Boston.
And when you talk bullpens, the Yankees' bullpen is insane; with Albertin Chapman throwing perhaps as hard as anyone ever, with Chad Green, Dellin Betances and Player Page for David Robertson just overwhelming hitters, that bullpen is averaging 11 strikeouts per nine. Get the Yankees early or don't get them at all.

The most representative pitcher of the entire playoffs might be Washington's Max Scherzer. His astonishing assortment of pitches -- a 95-mph fastball, one of the most dominant sliders in baseball and a back-breaking changeup -- makes it all but impossible for hitters to string hits against him. Scherzer led the league in WHIP (0.90) for the second straight season, and he allowed an astonishing 5.7 hits per nine innings. That's the lowest total in baseball since Pedro Martinez in 2000 ... and the seventh-lowest all time for a qualified starter.
So how do you get to Scherzer? That's the challenge. He doesn't walk many either. You have to take advantage of his mistakes; Scherzer has been somewhat home run prone the past couple of years, and that's probably a hitter's best bet.
But that isn't just true for Scherzer; hitters across baseball will spend these playoffs facing 100-mph fastballs and exploding sliders and gravity-defying curves. They will undoubtedly be swinging hard and hoping for mistakes.
Hitters in the long, wonderful history of baseball have always faced tough odds; the famous saying goes that if you fail to get a hit 70 percent of the time, you are going to the Hall of Fame. This is part of what makes the game great, that striving against a pitch that is on you in less than the blink of an eye and eight fielders set up to get you out should you actually hit the ball. The challenge for hitters is greater than ever. The ball is on them faster than ever. The fielders are placed better than ever.
Watching them find a way to beat those odds will be fun.