Colorado Rockies 3B Nolan Arenado a star in the making despite poor walk rate

When I was on Beyond the Box Score’s podcast a couple weeks ago talking about the Rockies, host Bryan Grosnick asked me what I would do to right the ship if I were the Rockies general manager. I answered by saying something about moving valuable but marginal players at the trade deadline in an effort to get younger and better within the next two to three years. If asked again, this is what I would say: give Nolan Arenado a lifetime contract for however much money he wants. That is all to say that I like Arenado very, very much. He’s good at just about everything he does on the baseball diamond. Just about.

Nolan Arenado has one major flaw in his game—he doesn’t take walks. He’s also not a great base runner and probably won’t steal 20 bases in his entire career, but he’s not a bad base runner, and stolen bases aren’t that important. Those aren’t flaws though. They are things he's not good at that having little to do with what he should be good at. But Arenado is demonstrably bad at taking walks, and that's important because the base on balls is a component of batting production.

From 2013-2015, Arenado has posted walk rates of 4.5, 5.4, and 4.4 (2015 stats through Friday’s game). In those seasons, the league average walk rate was 7.9, 7.6, and 7.6 percent. At his best, he’s been two percentage points below league average, while at his worst he’s been more than three percent below.

The lack of walks negatively affects Arenado’s on base percentage because it puts the burden of reaching base almost entirely on getting a hit. In Arenado’s rookie year in 2013, he had an altogether poor year at the plate. In particular, his OBP sat at just .301, which was well below the league average .318. He not only wasn’t walking, but he also wasn’t getting very many hits.

Just as Arenado’s poor walk rate in 2013 was a symptom of a poor season at the plate, his improved walk rate in 2014 was symptomatic of all around improvement. His .328 OBP propelled him above the league average mark of .314. On a broader scale, his all around improvement saw his wRC+ jump from 77 to 113. Arenado in 2015 is doing something different. He’s walking less than he did in his rookie season as well as his improved 2014. But he’s having his best offensive season to date, mostly due to his power surge.

One of the reason why Arenado’s walk rate has never been good is that he’s extremely aggressive. It’s not a problem this year because he’s mashing, but it was a problem as recently as 2013—though he was learning on the job then.

Arenado’s swing rate has fluctuated along with his walk rate. In 2013, he swung at 55.6 percent of all pitches, 71.6 percent of pitches in the zone, and 41 percent of pitches outside of it. In 2014, those figures dropped to 52.6, 69.2, and 37.3 percent, respectively. In 2015, however, each of those numbers have spiked. He’s swung at 56.8 percent of all pitches, 40.4 percent of pitches outside of the zone, and 76.3 of pitches in the zone. Each of those rates are well above league average. For the three-year sample we’re addressing here, the league has swung at about 46 percent of pitches, about 31 percent of pitches outside of the zone, and about 66 percent of pitches inside of it. Here’s a visual representation of the progression. You’ll notice the 2015 chart when everything becomes redder.

Arenado’s saving grace is that he’s better than average at making contact, so he doesn’t struck out much and he optimizes most plate appearances by putting the ball in play. Interestingly, Arenado’s contact rate this season is the lowest of his career. It’s at 80.9 percent, whereas in the last two years it was at 84.7 and 81.8 percent. However, his zone contact rate has gone up while his contact rate for balls outside of the zone has gone down. Arenado is a free swinger, but he is also excellent at making contact, especially on balls inside the zone.

Arenado is having success at the plate despite a poor walk rate. We can get a better sense of what that means by looking at historical precedent. Since 1961, there haven’t been very many players who have had a walk rate below five percent and a wRC+ above 100 for their career. There’s a correlation between being taking walks and being a good hitter. Part of that has to do with the exceptional eye good hitter’s exhibit, and another part of it has to do with pitchers being more careful against good batters and not giving them balls to hit in the zone.

	Years	Position	G	PA	BB%	K%	AVG	OBP	SLG	wRC+	WAR
Nolan Arenado	2013-	3B	315	1274	4.80%	13.40%	0.280	0.316	0.487	103	8.5
Adam Jones	2006-	Of	1168	4753	4.40%	19.10%	0.281	0.321	0.462	110	24.3
Ralph Garr	1968-1980	OF	1317	5456	4.50%	8.20%	0.306	0.339	0.416	106	12.2
Brian Harper	1979-1985	C	1001	3386	3.90%	5.60%	0.295	0.329	0.419	101	12.6
Howie Kendrick	2006-	OF	1151	4712	4.90%	17.30%	0.292	0.332	0.423	108	24.7
Yan Gomes	2012-	C	293	1058	4.80%	23.60%	0.267	0.307	0.445	110	7.7
Mickey Rivers	1970-1984	OF	1468	6026	4.40%	7.80%	0.295	0.327	0.397	106	23.9
Salvador Perez	2011-	C	469	1847	3.60%	12.40%	0.284	0.311	0.436	104	11.5
Alex Johnson	1964-1976	OF	1322	4948	4.90%	12.70%	0.288	0.326	0.392	103	8.4
Josh Harrison	2011-	IF	439	1417	3.30%	13.60%	0.282	0.315	0.420	105	7.1
Willie Davis	1960-1979	OF	2407	9728	4.30%	9.90%	0.279	0.311	0.411	105	53
Lou Johnson	1960-1969	OF	642	2176	4.80%	13.80%	0.260	0.313	0.394	105	6.9

The first thing that stands out in this list is that one third of the players are active and early in their careers. Arenado, Harrison, Perez, and Gomes each have ample opportunity to improve their walk rates at the plate. Kendrick and Jones have played enough so that their rates probably won’t change much between now and the end of their careers. They are reasonable comps for what Arenado's season could be if his walk rate stays the same, especially Adam Jones because of the power. While some of us—like me—are thinking Hall of Fame thoughts regarding Arenado, if he turns in a career like Jones or Kendrick (ca. 30 fWAR), he’d be the fourth best position player in team history. That’s a great career.

Arenado is well on his way to his best season yet, and he’s still only 24 years old. While there is not a lot of precedent of success with the walk rate he’s produced so far in his career, there are positive examples. If Arenado ends up as the third base version of Adam Jones, I’ll be just as happy as the Rockies. But Arenado isn't destined to have a poor walk rate for his career. It’s possible to make strides. Troy Tulowitzki, for instance, posted an 8.4 percent walk rate in his rookie season; in his shortened 2014, it increased to 13.3 percent (before declining dramatically to 5.3 percent in 2015).

Nolan Arenado’s success doesn’t rely on an improved walk rate, but improving the only thing he’s really bad at—as long as it doesn’t make him too conservative at the plate—would go along way toward not just elevating him to superstar status, but keeping him there.