Ever since the Diamondbacks selected Max Scherzer in the first round of the 2006 draft, his potential has been readily apparent to everyone who has watched him pitch. Anytime you have a pitcher with significant fastball velocity and movement, and at least one very strong secondary pitch, the sky is the limit. Stuff is pretty easy to identify early on, but becoming an elite pitcher requires more than raw ability.

For the first few years of his professional career, Scherzer had a classic case of “he should be better.” He was a solid contributor in Arizona and in his early years in Detroit, but if you watched his stuff on any given night, you were left wondering why he was above average rather than great. The biggest hurdle for Scherzer was repeating his rather chaotic delivery to the point where he could utilize his stuff effectively day in and day out. Adding a curveball certainly helped, but the turning point came in mid-2012 when Scherzer figured out how to find a consistent release point. He never looked back.

Split IP ERA- FIP- K% BB% Before June 17, 2012 687.1 96 94 23.4% 8.2% Since June 17, 2012 601.2 71 69 28.7% 6.5%

There’s no question Scherzer has grown into a much better pitcher over the last three years, and the change is apparent even if you want to adjust my somewhat arbitrary June 17, 2012 cut point. The seven-year, $210 million contract he signed last winter to join the Nationals is a good indicator of that growth. Most observers thought it was a fair value when you factor in the deferred payments, but even for those people who considered it to be an overpay, the message was clear: Scherzer had become one of the best pitchers in the league.

One of the downfalls of signing players to big free agent deals is that you’re almost always getting the player coming off his peak and rarely heading into it. Seven starts into Scherzer’s deal with the Nationals, he’s pitching better than he’s ever pitched. He’s at 1.9 WAR in 49.2 innings (1.6 RA9-WAR) and is projected to finish with 6.6 WAR according to our Depth Charts which use ZiPS, Steamer, and our own playing time estimates. If you wan to play the on pace game, he’s tracking toward 8-9 WAR this year.

Even if you’re more inclined to believe the conservative of the two numbers (and you should), he’s still on track to have his best season as a professional and there’s one major difference in his game that’s driving it. Scherzer stopped issuing walks.

Scherzer’s career low walk rate was 6.7% heading into 2015 and over the previous four seasons he’d been between 6.7% and 7.6% each year. That’s not an incredible mark, but given his ability to miss bats and limit damage, it made him one of the best dozen pitchers in the league. This year, Scherzer’s cut that walk rate to 3.1% while posting a strikeout rate identical to his 2014 mark. Scherzer was one of the best pitchers in the league when he had a 6-7% walk rate and over the first six weeks of 2015, he’s cut that in half while sacrificing nothing else that makes him great.

Whenever you see a change like this early in the season, the natural reaction is to look for reasons to explain why it’s happening. It’s human nature to search for explanations. We’re all in agreement that Scherzer was great before and if he’s actually cut his true talent walk rate by half, he’ll be even better. The question is how much we should believe a significantly different walk rate after just 50 innings of work.

The most obvious explanation is strength of competition. Scherzer moved from the AL to the NL and we would assume that he’s having an easier time avoiding walks because there are pitchers getting plate appearances in the Senior Circuit.

So let’s compare apples to apples and remove the pitchers from the equation. He faced four pitchers in 2014 and 16 in 2015. Let’s compare his walk rate against position players only. The spread actually gets bigger because one of Scherzer’s six 2015 walks came against a pitcher.

Year BB% vs Position Players 2014 7.0% 2015 2.8%

So that’s not a satisfying explanation. It might make sense that Scherzer would have an easier time in the National League because of the pitcher, but with respect to walks, that hasn’t moved the needle yet. What about the quality of the position players in general? Maybe Scherzer’s just facing weaker hitters who are less likely to walk. After all, it’s only been seven starts and sometimes it takes a while for things to even out.

To compare, I looked at the preseason projections for all of the position players he’s faced this year and weighted them based on how many times he’s faced them this year. Then I did the same thing for 2014 but I used their full season statistics to judge their ability. I recognize that this isn’t exactly a perfect methodology, but I didn’t have a way to assess their true talent (i.e. projection) at the moment they faced him last year, so this will have to do.

Year Opponents’ wOBA Opponents’ BB% 2014 .313 7.9% 2015 .311 6.9%

This provides a little support for the quality of competition hypothesis. The hitters aren’t drastically different in terms of overall production, but the 2015 group is projected to walk less than the 2014 group did by about a full percentage point. We can say that some of Scherzer’s decreased walk rate is based on slightly less patient opponents. Yet there’s more to explain. Is Scherzer doing something that might lead to fewer walks?

Looking at his plate discipline numbers suggest that he is. He’s throwing more strikes and inducing more swings overall, but he’s particularly getting batters to chase more often when he leaves the zone, and they’re not making contact.

Season O-Swing% Z-Swing% Swing% O-Contact% Z-Contact% Contact% Zone% 2008 27.1 % 64.2 % 47.1 % 54.1 % 79.7 % 72.9 % 54.1 % 2009 27.5 % 63.2 % 46.7 % 64.9 % 82.9 % 78.0 % 53.6 % 2010 29.2 % 59.7 % 45.4 % 66.2 % 84.2 % 78.8 % 53.1 % 2011 28.2 % 63.3 % 46.2 % 64.0 % 84.3 % 78.3 % 51.3 % 2012 28.8 % 65.2 % 47.7 % 59.4 % 79.8 % 73.8 % 51.8 % 2013 29.3 % 63.4 % 47.0 % 60.7 % 79.8 % 74.1 % 52.0 % 2014 29.8 % 64.6 % 47.9 % 60.3 % 81.8 % 75.3 % 51.9 % 2015 35.8 % 69.2 % 54.2 % 56.4 % 82.8 % 74.9 % 55.1 %

All of this fits the end result. More strikes in general and more swings and misses against pitches outside the zone should lead to fewer walks, almost by definition. We know that these types of statistics become more accurate indications of future performance sooner than most statistics, so the fact that his lower walk rate is being led by underlying changes in his plate discipline marks is a point in his favor.

The other thing that jumps out is that Scherzer is throwing more fastballs this year. The difference is somewhere in the 5-8% increase range depending on your classification of choice. Generally, it should be easier to locate a fastball than breaking balls and changeups, which could help Scherzer avoid walks when he gets behind. The other potential difference is the catcher’s ability to frame, but he threw mostly to Alex Avila last year and has thrown mostly to Wilson Ramos in 2015, both of whom grade out slightly above average in the season in question.

Looking at the entire picture, there’s nothing about Scherzer’s improved walk rate that looks out of place. It’s always good practice to include regression toward the mean, but the fact that Scherzer has posted a 3% walk rate for 50 innings probably tells us that his true talent walk rate has improved this year. It’s unlikely that the entire 4% drop is attributable to improvements made by Scherzer, but there’s enough evidence to suggest he has gotten at least a little bit better.

Even minor improvements for Scherzer are noteworthy at this point considering his recent track record. The Nationals paid handsomely for his services this offseason with the idea that he’d anchor their rotation after some combination of Stephen Strasburg, Jordan Zimmermann, and Doug Fister hit free agency. The deal made a lot of sense for the Nationals even if you assumed Scherzer was entering a slow decline. After watching his first few starts in 2015, it looks like he might have a little more time left among the Cy Young candidates, as he continues to hone his craft.