If Adrian Gonzalez Played For The Red Sox Last Year...

Using a few of the park/league adjustment resources I mentioned earlier today, I decided to look at how Adrian Gonzalez's plus-quality 2009 campaign in Petco Park would have looked like if he played for the Red Sox last season.

Playing for the Padres in 2009, Gonzalez put up a .277/.407/.551 line with 84 1B, 27 2B, 2 3B, 40 HR and 119 BB. That was good for a .402 wOBA. Let's look what happens when we change parks and leagues, keeping the low .280 BABIP stable (.310 career BABIP).

Petco Park adjustment (divide)


Fenway Park adjustments (multiply)


Combine these adjustments with the change of league adjustments and you quickly notice why Boston covets Adrian Gonzalez, who put up a .274 ISO playing 1/2 his games at Petco last season (click to enlarge):


I'm not exactly sure how the slugging percentage would change, but if Adrian Gonzalez was playing at the exact same level for Boston rather than San Diego last season, his .277 BA and .407 OBP would have translated into a .324 BA and .435 OBP at Fenway. Where as Petco depressed run production by 25.9% last season, Fenway bolstered it by 7.2%. A change of scenery between Boston and San Diego last year would have a 33% change in runs production in favor of hitters. Looking at the numbers, I have to conclude that the Red Sox's interest in Agon makes a lot of sense. In Petco, Adrian Gonzalez produced 48.9 Batting Runs Above Average (BRAA). If converted into Fenway numbers, Gonzalez would have, in theory, put up 70.7 BRAA. That would have made him a 8.3 WAR player, equally as valuable as 2009 NL MVP Albert Pujols (8.4 WAR, 72.1 BRAA). Gonzalez is one of the absolute best power hitters in the game and its a shame that he is forced to play in the worst power park in baseball (see Brian Giles). Even a move to a neutral park like Tropicana would do wonders for Gonzalez's career and impending free agency pay day in 2011.

I wouldn't project another .274 ISO season for Gonzalez (at least not in Petco), but a .285/.400/.530 line with 35+ HR to boot is more than reasonable. Remember that Gonzalez's numbers were held down by a poor BABIP and though Gonzalez should regress some towards his career norms (although at age 27, its possible that he could retain a lot of these power gains), the luck improvement in the other direction may cancel out some of those negative corrections. In other words, Gonzalez may be able to repeat his fantasy value in 2010.

Still, he's no Albert Pujols...right?

11 comments:

The 'Bright' One said...

dont know about pujols, but he's definitely no adam eaton

David "MVP" Eckstein said...

You didn't even read this post...did you?

The 'Bright' One said...

actually i did, 3 times over

David "MVP" Eckstein said...

Wrigley ranked third in runs distortion. Too bad all those extra runs went to the opposing teams last year....sigh....

Sexy Rexy said...

I didn't read your post but I can't imagine we can actually say a player would have done this based solely on park projections. We can project that he might have done something but how do you know the hitting coach would have changed something or how away games would have affected his numbers of how the quality of Gonzales' pitchers would have affected his numbers. Obviously PetCo deflates A-Gon's numbers but to say going to the Red Sox would have done this seems a but too far-fecthed at it seems that there are way too many variables to consider besides just changing parks and leagues

David "MVP" Eckstein said...

Well maybe if you actually read the post and hyperlinks...

The 'Bright' One said...

we all know hitting coaches dont do anything. do you think nate silver factored hitting coaches into pecota? i dont think so

Sexy Rexy said...

DME brought up a good point that the hitting coach does have some impact. Plus, even if you discount the hitting coach, there's still factors like opposing hitting and away ballparks. Maybe the AL competition is just better than the NL and would be more equipped to get AGon out?

I think there's a HUGE assumption that AGon would still make contact with the ball and still walk at the same rate as he did in San Diego and I'm not willing to make that assumption

Now if this was for fantasy purposes and AGon was on the Red Sox or if I was in the Red Sox front office, I would absolutely take the "risk" of getting him, but to say with absolute surety like you seem to be that he would put up these numbers based solely on ballpark factors seems to me you are taking an unnecessary leap

Triples said...

Nice article!

I'd hesitate to use ESPN's park factors, though. The formulation could certainly be improved upon. On top of that, these are "blanket" park factors- not all parks affect a hitter the same way. And with "blanket" PF, regression is always ideal. So that would change the outcome of your article by a wide margin.

I've got Gonzalez with a non-adjusted +42.3 RAA with the Padres. Once we "normalize" his component rates- (i.e. his singles, doubles, triples, HR, BB, SO) this changes his batting line to .293/.407/.591 and his RAA to +46.1.

If we translate Gonzalez's performance into Fenway Park (adjusting for league difficulty from the article you linked to, blanket LHPF, and changing the lwt values to fit the run environment), his line adjusts to .290/.398/.569. Instead of having an absolute lwtRC of +115 in a neutral park and league, he drops to a +110. His RAA goes from +46.1 to +37.6.

Adding in replacement level and a positional adjustment, Gonzalez becomes a +44.7 RAR hitter. Add in his UZR rating (can't translate into opps at Fenway so we'll keep it as is) and he's a +48.5 RAR, or 4.9 WAR, hitter in Boston.

And, naturally, since WAR is meant to be entirely context-neutral, he should be more around 5.7 WAR.

The difference between the source of PF changes Gonzalez's translation from being a 8.3 WAR player to a 4.9. That's huge.

David "MVP" Eckstein said...

I appreciate the suggestion, but I am still trying to get a grip on the THT park factor adjustments and how to utilize them (to be honest, I have both the articles book marked, but have not read them, but they seem to incorporate temperatures...)

Right now, I run all of this in a DIY excel macro I made, so until I get a better grip on how to adjust the numbers with THT's analysis, it would be pointless is reformulating my macro...

Anyways, as I point out in the end, a 50+ HR season is not exactly what I am calling for, but annual 35-40 HR seasons? Very reasonable.

I personally see Gonzalez as a +6 to +7 WAR player in Fenway next season

David "MVP" Eckstein said...

that is if he is traded to boston (which I hope he is not, because I have a bet with Cubsfan4ever ridding on them Signing beltre...)