Roster Review: John Jaso

By Jason Wojciechowski on January 28, 2014 at 10:21 PM

Look at this, we're like 10 days from pitchers and catchers and I'm eight players into my Roster Review series. World's Greatest Blogger awards ceremony is in April and I plan to be there to defend my belt. Also my mixed metaphor championship.

So we've been through this with Jaso and his role. Is he the designated hitter against righties, in a platoon with Craig Gentry wherein Gentry plays the outfield while Yoenis Cespedes designatedly hits? In a straight platoon with Nate Freiman while Brandon Moss gets to be a full-time player? In a platoon with Michael Taylor? Is he the platoon catcher? If he's the DH, is he also the backup catcher? Would Bob Melvin dare risk giving up his DH if Derek Norris got hurt and he had to move Jaso to catcher? I'm pretty sure I've stated my position on this, but: the risk of this happening one time in 162 games is well worth the flexibility of having an "extra" position player on the bench rather than having Stephen Vogt just sitting around doing nothing. Dump Vogt and you can carry Daric Barton or Michael Taylor, and you get the bonus of letting Derek Norris develop into a full-time player -- he was, after all, a legit prospect, twice cracking Baseball America's top 100 list, which is not something you can do if scouts think your bat is only going to work against lefties. He did hit shockingly poorly against right-handers last year (.149/.261/.184), but it was 135 plate appearances and ... wait, it was 135 plate appearances? And he hit that badly?

Fun question: how many consecutive singles would Norris have to hit in order to get his OPS against righties up to .700, the league average (basically -- it was .699) for catchers? Here's how many:

( (TOB + x) / (PA + x) ) + ( (TB + x) / (AB + x) ) >= .700 where x = singles
( (35 + x) / (134 + x) ) + ( (21 + x) / (114 + x) ) >= .700
(35 + x)(114 + x) + (21 + x)(134 + x) >= .7 * (134 + x)(114 + x)
2x^2 + 304x + 6804 >= 10,693.2 + 173.6 + .7x^2
13x^2 + 1,304x - 38,892 >= 0

And the Pythagorean theorem (the actual one, not the one we use to estimate team records) gives approximately 24.1. So since you need round number hits and we're dealing with an inequality, 25. He'd need 25 straight singles just to get that atrocious line up to .700.

I wonder whether I worked this out the most efficient way. Probably not. Who needs efficiency?

Who were we talking about? Oh John Jaso. Right so John Jaso should be utilized in such a way as to maximize the number of plate appearances that Derek Norris gets against right-handed pitchers. ... right? That's my takeaway?

Jaso himself, assuming he's all the way back from the bad concussion he suffered in July, has the potential to be a very good cog in the A's offense. He's likely to be underrated for all the usual reasons (not much power, especially for a designated hitter, platoon problems masking the fact that platoon problems can be dealt with by a savvy manager, the park), but he had a .291 True Average last year and is at .285 for his career, both of which are well above the average 2013 American League DH, who hit .267. Over a 450-PA season (figuring he's a platoon player), that's about a seven-run difference, so even if Jaso plays no catcher at all, if he hits like he's hit, he should be something like a 2.5-win player for $2.3 million (plus A.J. Cole, plus Blake Treinen, plus Ian Krol, but we don't have to talk about all that).

How does Jaso do it? Some stats (with minimums set at 200 plate appearances; Jaso had 249 PA, and 356 players meet that standard):

Stat Value MLB rank Notable player ranked lower
OBP .387 18th Robinson Cano
BB% 15.3% 5th Miguel Cabrera
Swing rate 36.1% 2nd Mike Trout
Chase rate 19.5% 17th Shin-Soo Choo

As you can tell by the swing rate "outdistancing" the chase rate, Jaso might walk very close to that patient/passive line. See also the Brooks Baseball characterizations of his eye (using a measure that combines his swing rate in the zone with this chase rate) and his approach (which is about patience vs. aggressiveness):

Pitch type Eye Approach
Fastballs good exceptionally patient
Breaking average very patient
Off-speed average very patient

Jaso saw pitches in the zone at a bottom-quartile rate in 2013 despite his .391 career slugging percentage and .286 career BABIP. He won't hurt you, in other words, but pitchers still did not come into the zone against him. At some point, I'd expect that to change, and if Jaso doesn't adjust back, whether because he struggles to adjust his approach or because his physical tools simply don't allow him to take advantage, he could find his walk rate taking a real hit without a concomitant rise in batting average and/or power. On the other hand, a lot of pitchers seem to fail to take my/Sean Doolittle's advice regarding pitching being easy, so maybe they'll continue to throw Jaso junk and try to paint the black instead of coming right after him with their best heat. Baseball is a weird institution that way.