Pitcher Spotlight: Jacob Nix’s MLB Debut

There was an MLB debut last night and we should talk about it. After boasting a 2.05 ERA and 0.91 WHIP in Double-A this season, Jacob Nix played his first career major league game, returning a marvelous 6.0 IP, 0 ER, 4 Hits, 2 BBs, 4 Ks line for the San Diego Padres. Does this mean he should be added in your NL-Only league or maybe even that office 12-teamer? Or was this just a debut that went well and should be ignored?

I’m going to make this easy for everyone. Nix does not have a Top 20 ceiling. He also isn’t the worst starter to consider in 12-teamers. There are two major strengths to Nix’s approach that could propel him to fantasy relevancy, but there is a significant flaw that makes me question his floor. That’s what I’m going to cover here and let’s start it off with one of his strengths: his fastball command.

Fastball Command

I was very impressed with how well Nix was able to move his fastball to both sides of the plate, while consistently having success up in the zone. With a left-handed heavy lineup, I loved watching Nix easily place fastballs up-and-in to jam Odubel Herrera:

And Asdrubal Cabrera:

While doing the same on the opposite side of the plate as he faced Maikel Franco:

This is a fantastic trait. I preach often how James Paxton, Sean Manaeaand David Price hinge on nailing the up-and-in corner of the zone to right-handers and the same applies to non-southpaws as well. It’s how Ervin Santana has made a career through the years and to see Nix do this out the gate at 95 mph is an excellent attribute.

I should correct that. Nix was hurling 94/95 mph in the opening frame, but as his adrenaline wore off, he was sitting with a range of 91-95. Expect around 93 mph with enough in the tank to push 95 mph when needed.

Back to his command. I should note that this a one-game sample and it’s often difficult to assess if this game’s command will be apparent in future outings. I don’t think this is the case here because of something you won’t find in the box score.

I love his mechanics.

You need another GIF to get a reference point. Don’t worry, it’s what I do:

There are two elements of his delivery that make a believer. The first is its simplicity. There’s nothing violent, it’s smooth, has repeatability, glove comes up, back leg collapses, arms come up, push towards home, bada-bing-bada-boom here’s the pitch and I can do this all day.

The second part is his stride that leads to his delivery. This isn’t your Jake Arrieta or Adam Ottavino landing foot off center, Nix glides straight toward the plate without deviation, preventing him from throwing cross-body. He lands perfectly straight without falling off toward first-base, a product of his excellent a north-south release that has his full momentum going toward the plate.

Why is this good? It means that he can adjust easily to locate in all parts of the zone. I talked about the same thing in Noah Syndergaard’s MLB debut back in 2015 and while those pitchers are wildly different, this similar characteristic will mean they share one statistic: a low walk rate.

There’s a difference between a low walk rate and good command, though. Mechanics give us the ability us to understand why Freddy Peralta’s two walks in his debut were questionable for sustainability, while Nix’s two walks Friday night may be a common thread, if not lower in future outings. With Nix’s delivery, I’d be surprised if it doesn’t sit under a 7% rate through the year and how his 4.5% mark in Double-A makes plenty of sense.

With the actual heater itself, the pitch isn’t enough to turn Nix into a strong asset. It creates the sandbox for his repertoire to play in, but it doesn’t create the castle. He needs an offering – if not two – to properly take advantage of his elevated fastballs on both sides of the plate.

The good news is that he has one in his changeup.


I don’t want to get too ahead of myself here, but I really liked this pitch. I think it has the potential to be a 20%+ whiff offering and opens the door for Nix to go full two-pitch if he has faith in it.

I think you’ll quickly understand. Look at this swing-and-miss to Odubel Herrera:

And this pitch fading along the outside corner for a weak flyout to left:

At first I thought Nix was only saving it for left-handed batters, but instead he whipped it out against Jorge Alfaro:

And Rhys Hoskins:

This. Is. Filthy.

I absolutely adore watching pitchers display confidence to throw changeups against batters of the same handedness and to see Nix execute it twice as a putaway offering is as good as it gets.

There is some hesitancy. Despite throwing 88 pitches in this game, Nix only turned to this slow ball twelve times. He tried to incorporate it early, but didn’t have the feel right away, either spiking it in the dirt or poorly realsing it, resulting in a changeup that floated well outside to left-handers. I’m willing to wager this was a product of jitters as he found it later in the game and excelled. I’m hoping he uses it over 30% of the time moving forward (even pulling a Trevor Richards and going 40% would be interesting!) and if Nix is going to take a step forward, it will be heavily on the back of this pitch.

I need to emphasize that last point as we transition to Nix’s biggest flaw. We’ve talked about his fastball – it’s good but not a gamechanger – but we haven’t talked about his final offering. Nix needs his changeup to be the focal point of his arsenal because if it’s his curveball, well, bad times are coming.


Every pitcher needs a secondary pitch they can trust to throw often for strikes. You might look at the results and think Nix has this in his curveball – he threw 19 in yesterday’s game with 11 landing over the plate. That’s a 58% zone rate! Here is what that looks like:

It looks fine and that’s pretty much what it is. Fine. It doesn’t have much movement or deception and unless he’s spotting it like he did here at the very bottom of the zone, it’s bound to run into trouble.

For example, here are some of the deuces Nix threw yesterday that were put into play. First one from an 0-2 pitch that turned into a single:

This one was hit so hard it couldn’t be turned into an out:

And another that went Nix’s way as the ball found the ground and a glove:

These aren’t good curveballs and I’m worried how reliant he was on the pitch to march through six frames. This hook was thrown over 20% of the time and it really should be used as a surprise early strike-getter, maybe around 10% at most and not a central part of his gameplan. At the same time, Nix’s changeup wasn’t working right away, which forced his hand, but seeing a 100% contact rate and zero whiffs on nearly twenty thrown is at the same time not surprising and very startling.


I’m a little conflicted about Jacob NixI love the foundation he sets with his mechanics and fastball, but his secondary stuff needs polishing. His changeup has plus-plus potential, but he needs more confidence to give it the larger spotlight. Meanwhile, his curveball is a liability and if he is forced to use it often, it could result in plenty of poor outings.

I’d consider Nix as an intriguing play for 2019 and beyond as it’s possible he finds a different third pitch, while giving him time to develop his changeup. His fastball command will prevent frequent mistakes and hold back free passes, which could turn him into a decent backend starter in 12-teamers as soon as next season. For now, I’d consider Nix only as a streaming option against weak lineups rooted in his changeup upside and fastball command.

We hoped you liked reading Pitcher Spotlight: Jacob Nix’s MLB Debut by Nick Pollack!

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Nick Pollack is the founder of PitcherList.com and has written for Washington Post, Fantasy Pros, and CBS Sports. He can be found making an excessive amount of GIFs on twitter at @PitcherList.

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Thanks Nick. Great write up.