Nationals Baseball: What's the worst that could happen : Gio and HRs

Thursday, December 29, 2011

What's the worst that could happen : Gio and HRs

Steven from FJB, noted that while Gio's HR numbers are low they may not be driven by a low GB%, but instead a particularly low (re: lucky) HR/FB percentage, helped in part by his home park.  The early projections expect a increase in rate to say 9.3%. Given roughly the same number of FBs that would lead to about 4 more homers. Is this real?

Well, as far as I think, that's the worst case scenario. Gio's rank in HR/FB does follow pretty closely with his rank in GB%.  (2010 13 out of 43 qualified AL pitchers in HR/FB, 13/43 in GB%; 2011 18/42 and 15/42).  No, that isn't the best way to judge these things, but it shows that he isn't out of whack when it comes to these stats. It even suggests that he may be doing just right.  Of course the home and road splits can't be ignored. In 2010 Gio had a HR/FB rate of 6.4% at home and 8.6% on the road, in 2011 the difference was 8.2% to 9.8%.  Obviously the park was helping him. So what to believe?

Just to get an idea of how bad he could be in Nats park, I went ahead and pulled his worst FB% in the past 2 years (38.2% 2010 home), his worst balls in play (2.83 per inning 2011), and his worst HR/FB ration (the 9.8% noted above).   Put that all together in a 200IP season and you get.... 21 homers. (assuming my back of the envelope calculations are right).  So it seems like the projections are expecting the worst.  (well the worst that could reasonably be expected.) All this is also figuring he won't pitch any different in a different park while his splits suggest he did allow more flyballs at home.

The short of it, for those that don't like fancy numbers, is that while his home park helps him with home runs it's not to a degree that Nats fan should worry about it.  My expectations are that he will give up a couple more homers.  There's just no way to deny that his home park helped him keep the ball in the park.  But just 4 more would be about the limit of what I think could happen.  There's virtually no chance in my mind that he suddenly gives up 25+ bombs and becomes a much worse pitcher because of that.


Wally said...

Do you have a sense what 4 more HRs makes his counting stats look like, assuming other numbers from 2011 hold constant? Is it just his 2011 xFIP of 3.73?

Harper said...

not even that - average runs per HR is about 1.4, so 6.4 runs more. Make it 7 and last year that only bumps his runs up to 77 and his ERA up to 3.43. I'd suspect that Gio would allow more runs per HR than average given his walk propensity but even at 2.0 he's not going to get to his xFIP.

Anonymous said...

How about you factor in the NL being a joke compared to the AL offensively?

His numbers will improve across the board, not only because he is getting better with age, but because it is easier to pitch in the NL.

3-3, 2.54 ERA, 1.19 WHIP, 61K/24BB
Those are his numbers in 10 starts against NL teams.

Next season we should expect 15-18 wins, ERA under 3, 200+ ks and about 80 walks

P.S.: Gonzalez is still better than Jair Jurrjens

Harper said...

Anon - just trying to isolate the HR issue. Really there are a bunch of things pulling his stats in all sorts of directions. 10 games really isn't enough to make a judgement one way or the other (I could point out that I think he's only faced one good offensive NL team - 2010 Cincy). I think he could hit your numbers but will probably just miss on ERA, something like 3.05 to 3.10.

As for Jai Jurrjens, we'll have to come up with a friendly bet. Like I'll have to drive a Geo if Gonzalez is better and you'll have to become Janonymous.

Steven said...

You're forgetting that most of the time balls that almost become homers usually instead become outs. So it's not just 4 more homers, it's likely 4 fewer outs. And then the impact isn't always perfectly linear. If he gets gunshy, starts to nibble, and/or gets tired pitching in a lot of 30-pitch innings, you could see a disproportionate impact on his overall numbers.

It's like the Petco effect in reverse. Aaron Harang's improvement from GABP to Petco can't be quantified entirely in park effects. Some of it is about the pitcher being able to change the way he pitches.

Anonymous said...

I'm going with the stats against NL-- 10 starts is a good beginning bit of data and I'll take the 2.54 ERA any day. Not pitching 3-4 AB's against a DH will offset the park change, I believe.


Anonymous said...

Has anyone actually checked the outfield dimensions and compared both fields? I just did:

Left Field - 330 feet
Left-Center - 367 feet
Center Field - 400 feet
Right-Center - 367 feet
Right Field - 330 feet

Left Field - 337 feet
Left-Center - 377 feet
Center Field - 402 feet
Right-Center - 370 feet
Right Field - 335 feet

Nat's Park is BIGGER in EVERY dimension in the outfield.

I would argue that his HR/FB numbers at home would remain the same or even DROP slightly.

Anonymous said...

Steven, I think you're reaching a little. Four more homers over the course of 100+ home innings will cause Gio to fundamentally change who he is as a pitcher? If so, there's been a massive miscalculation in the guys makeup evaluation.

I'm much more concerned about MCCatty trying to fix his first-pitch strike percentage to bring down the walks by throwing more fastballs only to have hitters tee off on first-pitch fastballs and having his hr% take a much bigger hit than the projections would suggest.

Allison said...

Chaos - I agree. I think it will more than offset any park differences and we will see stat improvement. Whether he improves relative to league is what will really tell us if he's improving though. It's not enough just to move AL -> NL and get better. You should.

Anon - that may be true but you can't go by just dimensions. The way the park is built can effect wind, sun, etc. Also at one point Oakland's fences actually drops back faster than the Nats then level off creating a very deep CF area. Oakland also has very high fences in RC and LC. It's best to check out park effects over a number of years to get an idea. (the end result for Oakland - it does depress HRs, Nats park is pretty average)

Noah said...

The primary reason Oakland is a pitcher friendly ballpark is due to the fact that the foul ball terrority is enormous relative to other fields. Pop-up fouls that would normally fall into the first 10 or so rows at another stadium frequently become outs in Oakland. While Oakland's park does give some significantly fewer home run's than Washington's it is mostly likely due to the increased opportunity for outs, not the distance of the outfield fences.

One interesting comp. would be Matt Garza. While the change in HR factor from Tampa to Wrigley is not as great as Oakland to Washington (but they still trended in the same direction), Garza's HR/FB% did decrease about 2%.

Harper said...

Noah- true but if it was only opportunity we'd see a similar decrease in all types of hits. We don't. We see a definite bigger drop in homers than singles and doubles if we look at the trend over a few years. But you're right in that the foul territory plays a big role. Should have caught that

Harper said...

Noah- true but if it was only opportunity we'd see a similar decrease in all types of hits. We don't. We see a definite bigger drop in homers than singles and doubles if we look at the trend over a few years. But you're right in that the foul territory plays a big role. Should have caught that

Anonymous said...