Think if you will, for a moment, about Jose Fernandez. What’s impressed you most about the healthy Jose Fernandez? Probably, it’s all the strikeouts, many of them coming on his breaking ball. This year, Clayton Kershaw has Jose Fernandez’s strikeout rate. Now veer off and think instead about Koji Uehara. The most amazing thing, probably, about Uehara is his impeccable command. This year, Kershaw has Koji Uehara’s walk rate. Finally, think about Tim Hudson. Hudson is among the league’s premier groundball specialists. He’s always been armed with a devastating hard sinker. This year, Kershaw has Tim Hudson’s groundball rate. This year’s Kershaw basically had the first three picks in the pitcher ability fantasy draft, and that explains how he’s allowed just 18 runs in ten starts, with seven of them coming in one.

None of them came in yesterday’s. Technically, Clayton Kershaw finished with a no-hitter, and not a perfect game. Realistically, he threw 1.037 perfect games, going above and beyond in the way that Armando Galarraga previously went above and beyond. And unlike with Galarraga, this wasn’t a start that came out of nowhere — with Kershaw, there was a sense of inevitability. You analyze his Wednesday start and you realize he didn’t do anything differently. He pitched like Clayton Kershaw, and this version of Clayton Kershaw was going to end up with at least one start of this kind. It was more a matter of when and where.

One is left with a variety of images. There’s Kershaw on the mound, standing straight up, arms to the sky. There’s Kershaw’s wife, watching along and feeling more anxiety than her husband. There’s everybody in the ballpark watching Kershaw’s curveball float and drop into the strike zone, hitter included. And there’s the slider, the wipeout slider responsible for the plurality of Wednesday’s outs. In all, Rockies hitters had the misfortune of batting 28 times. A dozen of those plate appearances ended with sliders, and of those, eight ended with strikeouts. All of the pitches were magical, but the slider stood out most, and given this opportunity, it’s worth a reflection on how Kershaw’s slider has progressed into arguably the greatest slider in the game.

Let’s watch a few examples. Here is an unfair pitch, thrown a number of times:

That’s just the best position player in the National League, no big deal.

That’s not the best position player in the National League.

That’s a fitting conclusion and a .gif of historical relevance.

The younger Kershaw was most known for his curveball. That much was justifiable, and as you might have noticed Wednesday, the curveball hasn’t gone anywhere. The curveball is outstanding, easily one of the game’s best. But over the years, Kershaw has folded in and developed more confidence in a slider. And the slider he was throwing in 2009 wasn’t the slider he was throwing Wednesday night. No, that pitch has evolved, and here’s an idea of how:

A breaking ball at 81 has gradually turned into a breaking ball at 87, to go with a fastball in the 90s and a curveball in the 70s. Between 2010 and 2011, Kershaw’s slider gained some power. The next year, it did it again. This year, he’s up another two ticks. Clayton Kershaw looked at what he did in 2013 and decided to try to be better than that. And, so far, he’s been true to his goal.

Laterally, the slider has always moved more or less like the curveball. Vertically, though, there used to be about eight inches of separation. Now there’s more than a foot, as the curve has stayed the same but the slider has tightened up. The slider, now, has less drop than ever, but it’s also faster than ever, which makes for a good trade-off. Understand that, over the years, the fastball has kept the same velocity. The curve has kept the same velocity. The slider has changed on its own, and this season to date, batters have missed it with more than half of their swings.

It’s not just the speed of the pitch that’s been changing. It’s also the location, which is evidence of Kershaw’s improving command. Courtesy of Brooks Baseball, let’s look at Kershaw’s rates of sliders thrown in the zone’s bottom third, or below:

For a while, just over half of Kershaw’s sliders could’ve been considered low. Now it’s more of a 4-to-1 ratio, the result being that batters have swung more, and batters have missed more. Previously, 28% of swings at Kershaw’s slider hit the ball fair. This year, that’s at 21%. The pitch is getting more strikes and more whiffs, and it’s allowed Kershaw to be absolutely dominant against lefties and righties alike. Let’s look at a few career contact rates against Kershaw’s slider:

High: 78% contact

Middle: 82%

Low: 44%

From Baseball Savant, here are Kershaw’s 2014 sliders that have been contacted:

And here are the 2014 sliders that have been missed:

Kershaw has always had a good fastball, that he’ll use in the middle of the zone or up. He’s always had that curve that works as a change of pace, coming in around 20 ticks slower. He’s had a slider for a while, but he’s never before had this slider, and he was already amazing with his last one. Now, the slider is sharper. Now, the slider is more consistently coming in on a different plane, staying down after approaching like a regular heater. Elevated sliders, before, could’ve been hit with fastball swings, and they could’ve been hit with air under them. Now they just drop to the bottom of the zone or below, yielding little opportunity to do damage even given contact, which has grown increasingly rare.

A year ago, Clayton Kershaw won the NL Cy Young Award. He’s since dropped his FIP by 79 points. The reasons are complex and numerous, but among them is the continued improvement of his slider, which he keeps in his back pocket along with Public Enemy No. 1. Clayton Kershaw isn’t amazing because he basically threw a perfect game against the Rockies. Clayton Kershaw is amazing because you could see a game like Wednesday’s coming a mile away. Those are the games you can throw when you possess two of the best pitches of their type on the planet.