Mike Yastrzemski’s Breakout Is (Mostly) Real

September 9, 2020

There are a lot of reasons the San Francisco Giants, typically a contender now gone moribund, are hanging around the .500 mark. One is the breakout of outfielder Mike Yastrzemski, grandson of legendary Boston Red Sox Hall of Famer Carl. Hitting .294/.402/.563 for a 158 wRC+ and ranking second among MLB hitters with 2.3 WAR, Yaz: The Next Generation is a legitimate MVP candidate, though he’s likely stymied in that endeavor by Fernando Tatis Jr. But Yaz’s sterling 2020 campaign represents broad improvement in a number of areas to the extent that it’s likely that he’s truly established a new baseline of performance at age 30.

The natural inclination for the Orioles would be to think of Yastrzemski as the one that got away. Back in the 1987 Baseball Abstract, Bill James coined the term of “Ken Phelps All-Star,” referring to overlooked players who could play in the majors but for one reason or another did not have the full opportunity to prove it. Sometimes it was a limitation that teams just couldn’t overlook. Sometimes the player broke out past an age where teams could be bothered to care. Sometimes it was simply an inability to understand baseball performance. While the last seems a little mean, 1980s front offices were not particularly progressive in terms of baseball analysis. It’s useful to remember when we’re fighting over stuff like volatility of defensive measures in WAR or FIP vs. ERA that just a generation ago, drawing walks wasn’t widely accepted as both a real skill and a skill worth valuing.

But that’s not really Yastrzemski. This isn’t someone who was spending his mid-20s terrorizing Triple-A hitters and failing to get an opportunity; he put up a .688 OPS at age 24 and a .716 at 25. The last name certainly wasn’t giving him any more opportunities than he deserved. Perusing his minor league translations would give you the idea that his glove played enough to be a fifth outfielder for someone but that his bat had little of his grandfather in it.

ZiPS Minor League Translations – Mike Yastrzemski

Year	BA	OBP	SLG	AB	R	H	2B	3B	HR	RBI	BB	SO	SB	DR
2013	.219	.281	.326	215	22	47	10	2	3	19	16	60	5	0.2
2014	.222	.266	.360	553	59	123	24	8	12	56	27	156	11	-0.6
2015	.212	.268	.312	490	50	104	23	4	6	43	32	141	6	0.0
2016	.223	.294	.371	480	58	107	23	3	14	51	47	144	11	18.5
2017	.245	.304	.431	364	49	89	17	3	15	48	31	107	3	11.8
2018	.224	.297	.372	441	52	99	22	5	11	48	42	121	6	10.0

ZiPS, which uses minor league hit ball location to roughly estimate a ZR-type of defensive statistic, really liked Little Yaz’s defense, but as a hitter he only translated with an OPS above .700 on a single occasion. When the Orioles traded him to the Giants for another minor league veteran, Tyler Herb, few eyebrows were raised. Yaz started the 2019 season for Triple-A Sacramento, playing all three outfield positions. His bat suddenly came alive in May and in a 15-game stretch, he hit .442/.532/1.038 with nine homers. The Giants were struggling to get anything from their outfield at this point in the 2019 campaign, so why not take a look at Yastrzemski?

Giants Outfielders Through 5/24/19

Name	G	BA	OBP	SLG	wRC+	WAR
Tyler Austin	28	.268	.349	.589	142	0.6
Kevin Pillar	45	.232	.264	.384	67	0.1
Michael Reed	4	.000	.000	.000	-100	-0.1
Connor Joe	8	.067	.125	.067	-46	-0.2
Mike Gerber	4	.067	.125	.133	-32	-0.2
Yangervis Solarte	28	.206	.247	.315	44	-0.3
Gerardo Parra	30	.198	.278	.267	45	-0.3
Steven Duggar	47	.237	.286	.344	67	-0.3
Mac Williamson	15	.118	.211	.196	14	-0.4

When a player used mainly as a pinch-hitter is leading your outfielders in WAR and the dude with eight hitless at-bats is third, something’s going wrong. The Giants weren’t going anywhere at 21-29, and rather than do what a lot of organizations would do and simply trade for some random veteran outfielder or find Carlos Gonzalez‘s phone number, they decided to take a look at Yaz. This is something I feel that a lot of clubs, even some very progressive ones otherwise, don’t always do well: if you can’t get someone good, get someone interesting. And Mike Yastrzemski was interesting.

Yastrzemski wasn’t an instant sensation with the Giants or anything like that, but he showed enough of a pulse at the plate and defensively in Oracle Park’s large outfield to keep getting playing time. He truly his his stride after the All-Star break, hitting .287/.354/.562 in the second half.

As Andrew Baggarly and Grant Brisbee wrote when discussing Yastrzemski’s breakout, he did it in large part by feasting on two-strike counts more than most hitters did. More than half of his home runs (11 of 21) came on two-strike counts. This year, it’s seven of eight. As Baggarly and Brisbee noted, Yaz is no longer as worried about striking out.

That does not mean adhering to the longstanding and now somewhat outdated advice that hitting coaches always preached about a two-strike approach. Yastrzemski used to choke up, spread out, shorten his swing, expand the zone.

“But I don’t anymore,” he said. “Because the whole idea of hitting is to try to get off your best swing as many times as you possibly can and hope you run into one at any of those points. That mentality stays the same. I’m still trying to get my best swing off even when the guy’s trying to strike me out.”

Yastrzemski credited the Giants’ hitting group of Donnie Ecker, Justin Viele, and Dustin Lind for continually reminding him that there’s no shame in striking out, especially if you’ve taken your optimal swing and made a good swing decision.

So, Yaz is pretty good now. What does it mean from a projection standpoint? Just to see how much of Yaz’s outlook has changed, here are his 2021-2024 projections made at three points: after 2018, after 2019, and right now (or at least a few hours ago). To keep the comparisons as consistent as possible, I’ve instructed ZiPS to not reduce any playing time due to ability.

ZiPS Projection – Mike Yastrzemski (Pre-2019)

Year	BA	OBP	SLG	AB	R	H	2B	3B	HR	RBI	BB	SO	SB	OPS+	DR	WAR
2021	.227	.294	.373	440	51	100	24	5	10	47	39	120	5	80	8	0.9
2022	.226	.292	.362	425	48	96	23	4	9	44	37	112	4	77	8	0.7
2023	.224	.287	.350	406	45	91	21	3	8	41	34	101	4	72	7	0.4
2024	.222	.283	.341	387	41	86	19	3	7	37	31	91	3	69	7	0.2

ZiPS Projection – Mike Yastrzemski (Pre-2020)

Year	BA	OBP	SLG	AB	R	H	2B	3B	HR	RBI	BB	SO	SB	OPS+	DR	WAR
2021	.245	.313	.435	441	62	108	25	4	17	59	41	122	4	99	7	1.9
2022	.244	.311	.431	427	58	104	24	4	16	56	39	115	4	98	6	1.7
2023	.240	.305	.418	409	54	98	22	3	15	51	36	105	4	93	6	1.4
2024	.237	.299	.404	389	49	92	20	3	13	46	33	95	3	88	5	1.0

ZiPS Projection – Mike Yastrzemski (Now)

Year	BA	OBP	SLG	AB	R	H	2B	3B	HR	RBI	BB	SO	SB	OPS+	DR	WAR
2021	.259	.331	.480	487	74	126	27	6	23	73	49	143	5	115	4	3.1
2022	.256	.328	.478	469	70	120	26	6	22	70	47	136	4	114	4	2.8
2023	.254	.327	.476	452	66	115	25	6	21	66	45	129	4	113	3	2.6
2024	.251	.321	.464	431	61	108	23	6	19	61	41	118	3	108	3	2.2

In the eyes of ZiPS, the 2019 season was enough to turn Yastrzemski from a role player to a legitimate stopgap starter for a few seasons. In about six weeks of 2020, he’s done enough to re-write the headline once again. No, ZiPS doesn’t see future MVP contention being likely, but what he’s done is at least enough to change the expectation to that of an above-average player, one can make an All-Star Game in his better seasons (and certainly would have if we had one this year). He’s unlikely to maintain his current .360 BABIP, but he doesn’t really need to; his plate discipline has improved, he can play defense, hit some doubles and homers, and has hit .359 against the shift. The fact that he’s already 30 counts against him in terms of long-term evaluation — players like the seemingly ageless Nelson Cruz are the exception rather than the rule — but he’s a key part of San Francisco’s lineup and likely will remain so for at least a few years.

For a team trying to rebuild without a full teardown, finding a player like Yastrzemski is a boon to the club’s future outlook. And maybe he will be an MVP contender in 2021 and beyond; it won’t be the first time Mike Yastrzemski proved everyone wrong.

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Dan Szymborski is a senior writer for FanGraphs and the developer of the ZiPS projection system. He was a writer for ESPN.com from 2010-2018, a regular guest on a number of radio shows and podcasts, and a voting BBWAA member. He also maintains a terrible Twitter account at @DSzymborski.