Jimmy Nelson Climbs Mountain, Immediately Falls Off Cliff

In mid-May, I noticed some significant adjustments made by Jimmy Nelson, and detailed them in this post. Through Nelson’s first eight starts in 2016, he was showing dramatic alterations in his strategy against left-handed batters, and the results were looking mighty positive:

• 2015 vs L (334 PA): .298/.381/.495, 18.3% K, 9.9% BB, .376 wOBA
• 2015 vs R (418 PA): .198/.275/.293, 20.8% K, 7.7% BB, .255 wOBA

• 2016 (through 5/16) vs L (92 PA):
  • .205/.286/.407, 20.7% K, 9.8% BB, .299 wOBA
• 2016 (through 5/16) vs R (119 PA):
  • .224/.308/.365, 18.5% K, 8.4% BB, .296 wOBA

Facing lefties in 2015, Nelson mostly tried to pound the lower part of the strike zone, relying heavily on his sinker and his hard curve. Through those first eight starts this year, he was still throwing sinkers down-and-away to lefty batters, but he was also throwing four-seamers up and in, and transitioned from the hard curve to his slower version. While I noted at the time — and will reiterate now — that eight starts is an admittedly small sample, the alterations in Nelson’s strategy were both consistent and significant to that point.

As you can see in the numbers above, it was working. Nelson’s never going to be a big strikeout guy — and I didn’t expect major changes in that department — but his evolved repertoire was producing tons of soft contact, good for ninth-best in the league to that point. He also had the 15th-lowest line-drive rate, sitting at just 15.9%. Unfortunately, that success ended pretty much as soon as I published that article.

Against lefties, his strikeouts fell off a cliff, right as his walks were rappelling their way up that same cliff. His command issues caused serious problems against left-handers, and it’s easy to see why. Through his first eight starts, Nelson threw his fastball up and in to lefties. His ability to locate the pitch in that corner was effective, both in generating soft contact, and in setting up his curve:

Now, take a look at his rest-of-season fastball location against lefties:

Boy, I sure wonder why that didn’t work. Still, Nelson was bad against lefties prior to this small eight-start sample to begin 2016, so it’s not shocking that he lost his effectiveness as the season went on. The really scary thing is how he got annihilated by same-handed hitting, something that was not a problem for Nelson previously.

The weird aspect of this is that his K/BB ratio against righties didn’t change much, which means he was probably just giving up loads of hard contact, right? Well, yes and no. Nelson’s hard-hit rate vsR did jump from around 25.0% to 29.0%, but the real issue was the types of batted balls he was surrendering hard contact on.

From mid-May on, his home-run-to-fly-ball ratio against righties was an enormous 20.8%. Only two qualified pitchers posted worse full-season HR/FB rates when facing right-handers in 2016: Jon Niese and Jaime Garcia. By contrast, Nelson’s HR/FB ratio vsR in 2015 was just 8.0%, and sat at 10.7% when I wrote that post after his eighth start this year.

Against right-handers, I’d like you to simply check out his full-repertoire heat maps, first looking at his data through mid-May, when I last wrote about him:

Just so I’m not posting a gazillion heat maps, I’ll tell you that he was working the inner edge with his fastball and sinker. His offspeed stuff was largely delivered from the waist down, working from the middle of the plate to the low-outside corner.

From mid-May on, his hard stuff moved right over the heart of the plate — much like it did against lefties — while he almost exclusively worked low-and-away with his secondary pitches, resulting in a full-repertoire map that looks like this:

Without having to worry about getting tied up by inside heat, life got much easier for right-handers against Nelson as the season wore on. They could simply sit dead-red, like this…

…or they could wait for a slider to catch too much of the plate, seeing as they likely knew exactly where he’d be aiming it. For example:

The problem with Jimmy Nelson isn’t his ability to gameplan. He’s made significant alterations to his pitch usage since he debuted in pro baseball. He started off in the minors as a fastball/slider guy, then developed his sinker (now his primary pitch) and curveball, giving him a full starter’s repertoire.

The issue here is that it doesn’t matter how smart or coachable you are, if you can’t command your pitches to suit your strategy. In each of the past two seasons, Nelson’s BB/9 soared — from 2.47 in ’14, to 3.30 in ’15, to 4.32 in ’16 — while his HR/9 (0.78 in ’14, 0.91 in ’15, 1.25 in ’16) escalated right along with the walks. In fact, Nelson was one of just two pitchers to surrender at least 25 homers and 85 walks this year, the other being Francisco Liriano.

When I wrote about him back in May, Nelson looked like he was developing into a useful fantasy starter. At the time, he held a 3.51 ERA and a 1.17 WHIP, and while not all of his peripherals aligned with those surface stats, it seemed that a change in strategy was creating a pitching profile that generates consistent weak contact.

Unfortunately, all the strategy in the world can’t help a pitcher if hitters have a better idea where the ball’s going than he does.