Wily Peralta may have gotten the start on Opening Day, but if there was a guy who was supposed to anchor the 2016 Brewers rotation, it was probably Jimmy Nelson.
The big righty was coming off of a bit of a breakout season, settling in during his first full year in the majors in 2015 with a steady 4.11 ERA thanks in large part to the development of a big curveball and an effective sinker. The expectation was that Nelson would take The Leap and be a workhorse for a Brewers team that would need some innings-eaters in a rebuilding year.
Through his first 10 or so starts, that’s what looked to be happening. Heading into June, opponents were hitting just .222/.313/.373 against Nelson. He was carrying an ERA of 2.88, with 59 strikeouts to 28 walks in 72 innings. Never a big strikeout pitcher, Nelson was hitting his spots, inducing weak contact and keeping guys off base. He was tying guys up when working up-and-in, and getting them to chase low-and-away.
Then everything fell apart in June.
Nelson lost his touch, and suddenly those sinkers, sliders and curves that were being placed on the outside corner became batting practice fodder. As it turns out, a low 90s sinker that doesn’t sink and ends up middle-in or middle-middle is pretty easy for major league hitters to pull 400 feet.
From June on, opponents hit .295/.389/.463 against Nelson thanks to a pretty simple strategy – they laid off the breaking stuff and waited to pound the crap out of the sinker that was suddenly catching way too much of the zone. Nelson gave up 16 home runs in his final 21 starts, and thanks to 58 walks in those appearances, the bases were rarely empty. That led to quite a few outings where the Brewers were down by a large margin early – deficits the post-Lucroy trade lineup couldn’t possibly hope to make up.
If you found yourself saying running almost anybody out there instead of Nelson would've been a better option during the second half, it turns out you were probably right. FanGraphs says Nelson was exactly replacement level in the second half, putting up a WAR of 0.0. For the sake of comparison, Junior Guerra pitched a little more than half the innings Nelson did in the second half due to injury and was still able to put up a WAR of 1.0. Zach Davies (1.8), Matt Garza (1.2), Wily Peralta (1.1) and even Chase Anderson (0.8) were also better than Nelson after the break.
Usually in these offseason postmortems, we can take a look at the game logs and find something – anything – that would indicate some glimmer of hope in the late-season appearances to project optimism going forward. I looked hard for something like that with Nelson. I really did. The problem is he only managed to post three (3!!) quality starts after the All-Star break. He went 7 innings in his first start after the break and didn’t do it again the rest of the season.
By the end of the year, he was a mechanical mess. Take a look at his release points from his first start of the year, a gem in which he pitched into the 8th inning in what would be a tough luck 2-1 loss to the Giants:
That’s a pretty tight cluster, showing a pretty consistent release. Compare it to his last start of the year, a 5.1-inning disappointment in which he blew a 3-0 lead and saw Carlos Gomez take him deep for a three-run homer:
Oh boy, that’s not as pretty.
If you don’t know what you’re looking at, these are plots from the batter’s point of view. Horizontal differences in the graphs could be due to a number of reasons – maybe Nelson’s delivery was more side-arm than it was in his first start, or maybe he simply could have been working from the a different spot on the rubber that day (looking at the video of the two starts was inconclusive on this, thanks to the low camera angle in Arlington that made it hard to see where he was setting up). But Nelson’s release point was also significantly lower than it was in April, and the wide variety shows his trouble with pitch-to-pitch consistency.
Throughout the year, Craig Counsell and others commented on Nelson’s tendency to let things snowball. If there’s hope for him going forward, maybe it’s based on a total reset with a new season. Nelson’s StatCast numbers seem to show his stuff didn’t fundamentally change from 2015 to 2016, just the execution and placement of his pitches. There’s a chance a fresh start leads to a bounce back campaign, as has been the case when you look at his history in the minors.
While Nelson has flashed moments of being a dependable workhorse that could be a #2 starter on a good team, he's also often looked like back-of-the-rotation fodder. You can easily make fun of the Quality Start idea as setting a low bar, but even by those standards Nelson's only put up a QS in 43% of his career starts. The MLB average is 51%. That kind of inconsistency is why he was constantly labeled a back-end starter by the most widely-read prospect writers.
When Nelson has bounced back from down seasons before in the minors, improving his control and cutting down the walks was the key. Nelson led the majors in walks in 2016 (and HBP, for that matter). If he can find the same feel he had during the first two months of the season again, it would go a long way in giving the Brewers a solid mid-rotation starter as they start to work their way back to relevancy.
Statistics courtesy of Fangraphs