Quarterly Report: Masahiro Tanaka’s Dominance

Roughly a quarter of the 2014 season is in the books, and the sample sizes are creeping toward a representative level. Over the next couple of weeks, let’s take a somewhat deeper look at some of this season’s more noteworthy players and performances to date. “Noteworthy” doesn’t always mean “best”, though it does in most cases. Let’s kick it off today with a look at Masahiro Tanaka‘s first seven starts as a Yankee. (This article was written prior to his eighth start, on Wednesday night.) His 58/7 K/BB ratio obviously speaks volumes about his ability. Is his future success based almost exclusively on this solid foundation, or is there even more to him?

The raw traditional numbers are pretty impressive – 5-0, 2.57, with that superb K/BB ratio. Poke down just a little further beneath the surface and there’s even more good stuff. The best swinging-strike percentage (14.5%) in the American League. A much higher than league average ground ball rate. He’s the only ERA qualifier in the AL to average seven innings per start to date. It isn’t too early to state that Brian Cashman was in “under-promise but over-deliver” mode when he dubbed Tanaka a “number three starter” upon his signing. Only aces do what Tanaka has done over any seven-start stretch, let alone the first seven starts of their MLB career.

Let’s also consider the context of his performance to date – four of his starts have come at home, in a hitter-friendly yard with a 2013 park factor of 110.0, based on my own calculations utilizing granular batted ball data. According to this method, Yankee Stadium was the fourth most hitter-friendly park in the majors in 2013, behind Colorado, Boston and Milwaukee. It was the sixth most hitter-friendly park for fly balls, and second most for line drives. Two of his three road starts were at even more hitter-friendly parks – Fenway and Miller Park – and the other was at Toronto, versus their power-laden lineup. His home starts have been against the well-regarded offenses of the Orioles, Rays and, well, the Cubs. Overall, he has faced stronger than average clubs in more hitter-friendly than average venues.

It doesn’t take too long to identify a potential Achilles’ heel – vulnerability to the longball. Tanaka has given up as many homers – seven – as walks in the early going, and the one David Ortiz hit off of him is still in orbit.

So what do we have in Masahiro Tanaka? Is he “just” a strike-throwing bat-misser with a home run problem? That wouldn’t be a crime – Fergie Jenkins and Robin Roberts, to name two, rode such a package all the way to the Hall of Fame. Or might he be something even better – a superior K/BB guy who also manages contact very well, like the 2009-13 version of Clayton Kershaw? Let’s take a look at Tanaka’s 2014 plate appearance outcome frequency and production by BIP type data for some hints. Keep in mind that the sample sizes remain small, so most of the contextual information incorporated below is from the 2013 season. No matter – we’re not searching for exactitude here, just looking for some indicators.

Tanaka % REL PCT
K 29.9% 149 96
BB 3.6% 42 1
POP 8.2% 105 57
FLY 23.0% 82 8
LD 18.8% 91 12
GB 50.0% 115 90

FLY 0.357 1.250 237 114
LD 0.696 1.000 117 109
GB 0.262 0.262 113 125
ALL BIP 0.333 0.587 121 97
ALL PA 0.228 0.257 0.402 79 64 2.57 3.18 2.61

First, let’s look at the frequency table. Tanaka’s superior K and BB rates are the headliners here – his K rate is 149 percent of the 2014 MLB average, and in the 96th percentile of MLB pitchers, using 2013 data for context. His BB rate is as low as it gets, in the 1st percentile. His line drive rate is also very low, in the 8th percentile, though that is the most fluid of the frequency figures going forward, a clear regression candidate. His ground ball rate is very high, in the 90th percentile, and is likely real. He manages to pull off the odd combo of a very strong ground ball tendency and a higher than average popup rate, something accomplished by Tim Hudson in 2013. Frequency-wise, it’s a slightly less extremely grounder-focused version of Justin Masterson‘s profile.

Frequency is only one part of the story, however. The second table lists the production from and hints at the authority of the batted balls yielded by Tanaka. The actual production allowed for each BIP type is listed in the “AVG” and “SLG” columns, and is converted into run values, compared to MLB average and scaled to 100 in the “REL PRD” column. Estimates of context, i.e., ballpark, team defense, simple regression and luck are applied in the “ADJ PRD” column in an attempt to isolate Tanaka’s true talent. In the three right-most columns, his actual ERA, his calculated ERA (based on his ADJ PRD) and his “tru” ERA (adjusted for context) are listed. For the purposes of this exercise, HBP are excluded from the OBP calculation, and SH and SF are counted as outs. Again – this is relatively small sample, with much subjectivity in the contextual adjustments, so let’s not get caught up in absolute precision here.

What you see is a guy who has been pummeled in the air to date, to the tune of a .357 AVG-1.250 SLG. We shouldn’t overreact to this, as six of his seven HR allowed have been at Yankee Stadium and Fenway Park, both homer-friendly stadiums, and two of the homers in particular were fairly “soft” homers. The other five were legit and then some, in the case of one of them. It’s fair to say that he has allowed harder than average fly ball contact, though the adjusted for context 114 ADJ PRD feels much more realistic. Actual production allowed on both liners and grounders suggests harder than average batted-ball authority as well. So while batted-ball type frequency, thanks to his ground ball tendency, is a strength, the level of authority within each of those groups has been harder than average. Overall, the grounder tendency prevails, as his overall ADJ PRD – you might call it his adjusted contact score – on all BIP is a league average-ish 97. Add all those K’s and those few BB’s back, however, and you have a “tru” ERA of 2.61, almost exactly the same as his actual ERA.

How does this early estimate of Tanaka’s contact management ability measure up that of the game’s current ruling class of pitchers? Let’s take a look at this same data for the 2013 performances of Yu Darvish, Felix Hernandez and Clayton Kershaw.

Darvish % REL PCT
K 34.2% 172 99
BB 9.9% 128 87
POP 10.4% 137 85
FLY 31.2% 111 79
LD 20.1% 94 24
GB 38.3% 89 22
Hernandez % REL PCT
K 27.8% 140 95
BB 5.9% 77 18
POP 5.6% 75 24
FLY 25.1% 89 26
LD 21.6% 101 52
GB 47.7% 111 82
Kershaw % REL PCT
K 26.2% 132 93
BB 5.9% 76 16
POP 8.5% 112 69
FLY 24.0% 86 16
LD 23.2% 108 84
GB 44.3% 103 60

FLY 0.279 0.857 118 116
LD 0.648 0.898 102 109
GB 0.243 0.249 101 120
ALL BIP 0.309 0.536 101 107
ALL PA 0.193 0.272 0.335 72 76 2.83 2.81 2.93
FLY 0.264 0.682 85 101
LD 0.739 0.991 129 105
GB 0.227 0.251 93 101
ALL BIP 0.330 0.488 99 97
ALL PA 0.238 0.281 0.352 78 77 3.04 3.04 2.98
FLY 0.190 0.469 42 57
LD 0.571 0.671 69 87
GB 0.203 0.244 80 97
ALL BIP 0.265 0.376 61 79
ALL PA 0.192 0.239 0.273 53 65 1.83 2.04 2.52

Frequency-wise, two of the three, Hernandez and Kershaw, displayed 2013 K and BB rates somewhat comparable to Tanaka’s 2014 marks. On both the K and especially the BB side, however, Tanaka’s numbers are better, though they were accumulated over seven starts rather than over a full season. Hernandez and Kershaw also showed groundball tendencies in 2013, though again not as strong as Tanaka’s 2014 marks. Overall, Tanaka bests all three frequency-wise.

Authority-wise, it’s a different story. Two of the three, Darvish and Hernandez in this case, were in the same league average-ish neighborhood in 2013 where Tanaka resides in 2014. Darvish’s adjusted contact score of 107 was worse than MLB average, but when you strike out almost 35% of the batters you face, it’s not a big deal. Hernandez’ 2013 adjusted contact score of 97 exactly matches Tanaka’s 2014 mark.

Kershaw is a different animal, however. On top of his exceptional 2013 K and BB rates, he held hitters to a puny .190 AVG-.469 SLG on fly balls – after adjustment for context, that’s an amazing fly ball contact score of 57. He also yielded below average production and authority on liners and grounders, for an overall adjusted contact score of 79, best in the NL last season.

I feel comfortable conclusively stating that Tanaka is not Kershaw when it comes to managing contact. The peak version of Kershaw might never allow a homer as loud as the one Tanaka yielded to Big Papi earlier this season. Based on the limited data available to this point, Tanaka’s contact management ability appears to most closely match that of Felix Hernandez among this small group of elites, and that’s plenty good enough. With such incredible K and BB rates, it’s enough to make Tanaka a legitimate ace and Cy Young Award candidate.

Not to beat a dead horse here, but again – it’s only seven starts. Hideo Nomo struck out 55 batters over 41 innings in his first seven starts, on his way to whiffing an insane 236 batters in 191 1/3 innings as a rookie, before hitters began to gradually figure out his delivery. He settled in as a fine #2-3 starter, but wasn’t the dominant ace he first appeared to be. Fernando Valenzuela won – and COMPLETED – all of his first seven starts, posting a 0.29 ERA with a 61/16 K/BB in those 63 innings. He was very good for a few years afterward, but was never “that guy” again. We just might be seeing the best we will ever see from Tanaka right now, as he remains something new and different, as yet unseen by the majority of major league hitters.

We can certainly say this much about him, though. His splitter just might be the best single offering thrown by any starter in the game today. He has an amazing 25.7% whiff rate on it – over a quarter of the splitters he has thrown have resulted in a swing and a miss. His slider is a second viable whiff pitch (12.6%). He has utterly dominated the opposite hand, yielding a paltry .207-.225-.310 line to lefties to date.

Most of all, he just pumps strikes. Swings and misses with multiple weapons, a true, bona fide out pitch, a mastery of opposite-handed hitters – this is the stuff of which dominant starters are made. It’s early, but if he can stay healthy – a massive “if” for any pitcher these days – the Yanks should be able to chalk up this signing as a major win.

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Aaron (UK)
Aaron (UK)

(This article was written prior to his eighth start, on Wednesday night.)

Well a shutout with 4H, 0BB and 8K isn’t going to hurt too much.


What I thought. Not a bad time to write the article.