The Yankees have another star at shortstop

You might remember this: Didi Gregorius couldn't hit. That was his distinguishing feature. He could field, but he couldn't hit.
Gregorius was born in the Netherlands and grew up in Curacao. The Reds found him playing in a tournament in The Hague -- a city on the western coast of the Netherlands -- and signed him in 2007. Right away, Gregorius showed that he could play a breathtaking shortstop. And from the start, he had the bat knocked out of his hands at the plate.
The Reds traded Gregorius to the D-backs in a three-team deal in 2012. His role in that deal was described like this by The Associated Press: The D-backs "also received shortstop prospect Didi Gregorius." But former Arizona general manager Kevin Towers liked Gregorius a lot, even saying these words that followed the shortstop around: "He reminds me of a young Derek Jeter."
The Jeter comparison seemed silly at first. Gregorius still didn't hit. In 2013, his first year in Arizona -- a great hitters' environment -- he hit .252. The next year, it was worse. Gregorius hit .226 with a .290 on-base percentage.
That's when the D-backs traded Gregorius to the Yankees in a deal that The Associated Press described like this: "Arizona sent slick-fielding, light-hitting shortstop Didi Gregorius to the Yankees, where he becomes a favorite to replace Derek Jeter."
The script clearly called for Gregorius to be a good defender and a struggling hitter. Everybody said so.

Now, in 2018, Gregorius leads the American League in slugging and OPS. Yes, it's early in the year, but he showed flashes of this kind of hitting last year, so this doesn't feel fluky at all.
Gregorius has just four strikeouts in 49 at-bats. He is developing scary plate discipline (his 12 walks through 15 games is nearly half as many as he had in 2017). Gregorius has a lot of power. He suddenly looks like a younger version of Robinson Canó.
Earlier in the year, we were asking who the best left-handed hitter in the AL is. Well, it might be Gregorius.
Bundy's slider success
There was a time when scouts called Baltimore's Dylan Bundy the best pitching prospect in baseball. He seemed to be the complete pitcher -- a mid-90s fastball, coupled with a dazzling curveball, an overpowering slider and a promising changeup.
And then … well, it's hard to say what exactly went wrong. It's probably more correct to say that little went right. Bundy's mid-90s fastball sort of evolved into a low-90s fastball. The dominant strikeout stuff he showed as a 19-year-old was a lot plainer after he had Tommy John surgery. The consistent storyline was that Bundy was just about to break out -- and he had enough promising moments to keep that going -- but he never quite did. There were some who thought the Orioles should put Bundy in the bullpen.
Late last year, though, Bundy seemed to figure out something valuable -- throw the slider.
In 2016, Bundy didn't throw the slider. He was strictly a fastball, curveball and changeup pitcher. But as '17 went along, Bundy began relying more on the slider, and he had success with it.

This year, nobody is hitting Bundy's slider. He's throwing it about 27 percent of the time, among the highest percentages in baseball, and batters are swinging and missing more than one-third of the time. Hitters have a measly four hits off Bundy's slider (they're hitting .125), and only one of those was an extra-base hit.
Add in some success that Bundy is having with his sinking two-seam fastball (just one hit in seven at-bats), and you can see why the right-hander is off to such a great start. He has a 1.40 ERA, 31 strikeouts and seven walks. 
Is this it? Are we seeing Bundy become the star he was destined to become?
We'll see. The key with Bundy is how well he holds up. He had a 2.26 ERA through his first eight starts last year before tailing off. But it should be said that his peripheral numbers in 2017 -- things like strikeouts per nine innings and opponent batting average -- suggested that start was unlikely to last. This year, Bundy seems to be doing everything right.
Grichuk's early bad luck
Through his first 14 games with the Blue Jays, outfielder Randal Grichuk had an .077 batting average on balls in play. This is obviously a tiny sample size, but do you have any idea how hard it is to have an .077 BABIP? Only Philadelphia's Aaron Altherr (with a staggering .050 BABIP) has a lower one.
But here's the craziest part: Grichuk has been hitting the ball hard. His 12.8 percent Statcast™ barrel rate -- meaning 12.8 percent of the time he mashes the ball with an exit velocity and launch angle that should be an extra-base hit -- ranks ninth in the Majors.

How does someone hit the ball that hard with that little result? Well, it's a confluence of things -- bad luck, poor directional hitting, predictability, but mostly bad luck.
The biggest problem with such hard-luck hitting is how it affects the hitter's confidence. Grichuk was a big offseason acquisition. Quite a few so-called experts (including yours truly) predicted good things for him. Now, Grichuk is batting .071 and being "rested" to get his head straight, and this is a hard cycle to break.
You make the call
Here's a fun one to go over: On Saturday night in Seattle, during the third inning, the Mariners had a 3-0 lead and the A's were batting. With two outs, Marcus Semien drilled a hard line drive to left. Jonathan Lucroy -- not a speedster -- was on first, and he came all the way around to score.
Then, Semien, seeing the ball bounce away from Seattle catcher David Freitas, tried to score himself. Freitas made a spectacularly alert play, flipping the ball to Marco Gonzales, who tagged out Freitas to end the inning, as only one run scored.
Only not. The Mariners realized that Semien's ball actually bounced over the fence and should have been called a ground-rule double. So now, what do you do? Do you challenge and take the out (and the run) off the board and give the A's runners on second and third? Or do you concede the run, take the out and move on?

Seattle challenged and took the out and run off the board. Oakland scored three runs in the inning, so that backfired. But good decisions sometimes backfire. The question here is: Did the Mariners do the right thing?
The short answer is: Yes, probably, but it's more complicated than you might think. Most of the time, you would figure out run values. What is the run value of having runners on second and third with two outs? Is it less or more than a run? Well, it is less: The run expectancy for runners on second and third with two outs is 0.58 runs, which is obviously less than a full run. This seems open and shut.
But the truth is that win expectancy is more important here than run expectancy … and more elusive. Why is win expectancy the key? Well, the run value stays constant, but the game doesn't. We all can think of scenarios during a game where challenging there would be a terrible decision. Just one example: If this was the ninth inning, for instance, you would obviously not challenge the call, because the out would be way more important than the run, as it would end the game.
In this specific Mariners-A's scenario, Tom Tango figures that Seattle's win expectancy if the Mariners let the play go is 77.2 percent -- that's with Seattle ahead, 3-1, going into the bottom of the third.
But the Mariners' win expectancy if you go back -- up 3-0 with two runners on -- is 79.4 percent, a fairly sizable difference. So in this case, no matter how you look at it, Seattle made the better mathematical choice to challenge the play.