• Mizuno ST-X and ST-Z hit USGA conforming list
  • Will likely be marketed to mid-slow swing players
  • Pricing remains unknown for the probable early 2021 release


Two new Mizuno drivers hit the USGA conforming list on Monday – the Mizuno ST-X and ST-Z. As per usual, what we know is a combination of reasonable assumptions based on the provided images and some dot-connecting with prior Mizuno driver releases.

Starting with the ST190 (released fall 2018), Mizuno metalwoods began trending in a more competitive direction. It’s not that Mizuno lacked the technical know-how or design capabilities to manufacturer a tour-ready driver. Simply, it just wasn’t a point of emphasis.

So, the ST190 was a positive step and in January 2020, the ST200 line was arguably the first bonafide “tour-ready” flagship Mizuno driver.

So, where does that leave us now?


Based on images taken from the USGA’s conforming list, it appears that Mizuno is sticking with a familiar cast of characters.  If so, like the ST200x, the STx should target the golfer looking for something with a little more draw bias and higher launch and spin. Also, if the past is prologue, the STx will feature a slightly more upright lie angle and a square (if not slightly closed) face.

The primary visual indicator is the circular weight in the rear heel area. This likely pulls some discretionary weight that moves the CG to a location that makes it easier for golfers to square the face at impact. Also, it looks as though Mizuno is continuing its Wave sole technology. It’s reasonable to believe that this works in conjunction with face materials to maximize ball speed and produce its desired sound/feel at impact.

The marketing materials will likely suggest this is for mid-slow swing speed players who can benefit from a lighter driver with internal weighting to help mitigate the dreaded slice. But that shouldn’t exclude the STx automatically from consideration from a spot in the bag of better players. See: Mizuno staffer Chris Kirk.

Kirk gamed the ST200x during the last year on both the Korn Ferry Tour and PGA Tour.

If there’s a lesson here, it’s that preconceived notions of what gear you think will maximize performance may not necessarily be accurate.


Like the Mizun0 ST-X, the ST-Z features  (what looks to be) an interchangeable sole weight and Wave sole technology. The primary difference between the two looks to be the location of the weight and the absence of a ribbed (possibly polymer? rubber? goo?) section along the heel in the ST-X.

My hunch is this is the “Mizuno for the masses” offering of the ST series. The rear weight location suggests a neutral, higher MOI head. If so, the ST-Z takes the place of the ST200 and targets the golfer who is best served by a stable platform and mid-low spin with mid-launch characteristics.

Also, it should be noted that both the Mizuno ST-Z nor ST-X look to maintain Mizuno’s adjustable hosel system. We can’t tell, however, whether Mizuno altered or expanded on the number of settings.


But wait, didn’t the ST200 line have three drivers, not two? That is correct, sir. So, it appears something is missing. The most obvious answer would be a lower launching/spinning head with both an adjustable hosel and some moveable-weight technology. Previously, this was the ST200G. But, given the ST-X and ST-Z monikers, I’m guessing it will be the ST-Y. Unless, of course, I’m dead wrong, and it’s the ST-G. But, Mizuno is notoriously tricky to predict with product names. It’s not like the iron models follow any coherent numerical pattern. But it did give us the Donkey Shovel, so all is forgiven.

Generally, this timing would suggest something of an early 2021 official release, which is probably relatively accurate. No word yet on pricing, though the last time around, the ST200 and ST200X had a rack rate of $400. The ST200G was $100 more. From a value standpoint, if Mizuno can stick at (or close) to these price points, it could make for some intriguing possibilities for golfers willing to look outside the Big 4 for the next big dog.

We will update this article with additional information as it becomes available.

But in the meantime, what questions do you have?