Here is his question in a comment:
I am interested in your thoughts on Barry's preciptous decline. He hit well over 300 in his 14 games last September, hit that monster HR in Philly.
Now I see him taking first pitch fastballs for strikes (often the best pitch he sees). He doesn't seem to pull much down the line. And he doesn't seem to hit the ball squarley very often. I could understand losing his legs, losing his power, and there seems to be some power loss (but how to explain the monster shot in Philly?), but what explains the poor, inconsistent contact? And what happened to the left-center HR power? Thoughts?
Here is my reply:
I'm not so good on the physical parts since I'm no expert in observing baseball skills, particularly to the detail you note about Bonds. I happened to see Ishikawa launch one and from watching baseball for a long while, I know that such power doesn't come randomly like that, he has serious power (but then you can see his HR numbers and see that too).
That said, I can try to synthesize a "story" of what's happening to Bonds, based on what I've read and analyzing his stats. I'll try to give you an answer on this tomorrow.
Initially thoughts is that he is 42 years old, it's going to happen at some point, even to him.
To illustrate, Willie Mays power shrunk greatly from 1966 to 1967, going from 37 HR to 22 HR (or from 15 AB/HR to 22 AB/HR, or roughly a 33% drop in HR power), so a batter's skill can drop precipitously just in the off-season.
I also cannot prove this, and not wanting to sound like a conspiracy, I think that umpires - generally - have been squeezing his strikezone this year, either purposefully or subconsciously, because they, like many baseball fans, think he cheated, think he purposefully cheated, think that he is getting away with it, and possibly want him punished in some way. And the only way umpires can acheive any sort of "justice" in their minds, given this scenario (and I think it is only human nature, hence why I don't want to call it a conspiracy), is to call the strikezone like they normally do it instead of giving him the benefit of a doubt - and maybe some will squeeze him further. That forces him into more counts that favor the pitcher, meaning the pitchers can be that much less predictable in what they throw, meaning he will make less consistent contact.
In addition, pitcher don't have to throw down and away pitches as often to try to get a strike by him, if they can mix it up more, they can throw less of them and challenge him more because he wouldn't be expecting it. That would result in less left-center hits and HR (this is stretching my knowledge but I gave it a shot).
I compiled Bonds' AB and BB (and thus PA) stats for 2003-2006, covering how many PA he had with each count (0-0, 0-1, 0-2, etc.). And well, my theory is just wrong, at least from the data.
What I found was that his ABs in any particular count is about the same across the board through the years, so he is not taking a lot more strikes as I had hypothesized, so I was wrong there. So he is taking counts at about the same percentage of times that he did before, taking account of only the times he actually had an AB vs. a BB.
He is putting the ball in play at the same percentage of first pitch, just down slightly (13.4% vs. previous three seasons of 14.4%, 16.4%, 14.3% or 1 AB per 100). There is a slight increase in the number of AB and PA in 0-1 counts, though again about the same as before (43.3% vs. 42.6%, 40.2%, 31.0% AB; 37.9% vs. 36.1%, 29.3%, 29.4% for PA). So I was correct that there were more strikes that he is either taking or swinging, but that is only 1-2 AB/PA per 100, not a really big change and certainly not big enough to drop him from a .350+ hitter to a .250 hitter.
And generally, there are more counts where there is 1 or more strikes, just not greatly so: 0-1, 1-1, 1-2, 2-1, 3-1, 3-2. But there were about the same, maybe a little less, for the 0-2 and 2-2 counts. So no "conspiracy" as I had suspected, probably either just old age affecting him or perhaps he couldn't prepare for the season like he normally does that that threw him off his game/batting stroke. Positives that have been happening in the latter part of the season include his stealing some bases and comments by writers that he was making plays on balls that he wasn't making earlier in the season (though still poor overall). That would support the theory that his conditioning was off at the start of this season and that he has been slowing rounding into "playing" shape.
However, that has not been showing up in his batting stats. His batting average, OBP, and OPS has been in a general downslide each month of the season. The only plus is that his SLG is up this month but it was down horribly last month, to low .400; for contrast, that's where Vizquel's SLG is for this season!
And managers are still afraid of him: he's still getting close to the same percentage of intentional walks as he was in 2003 (9.8% vs. 11.3% of PA) though nowhere close to 2004 (19.8%). That's still a lot because for any other batter, a TOTAL walk rate of 10% of PA is very good and here he's being given these IBB at that rate and he still gets his other walks, some of which eventually become intentional but are not recorded as such.
In addition, he has hit way better at home (.256/.474/.545/1.019) than on the road (.226/.426/.425/.851). So perhaps the road fans are getting to him more than he lets on. And with a nice 9 game home stretch from tonight (after Giants beat dem Bums! 7-3!), his stats will look a lot better by the end of the month than it does now.
So it looks like time has finally caught up with him, just like it did with his godfather, Willie Mays. Mays went from hitting .288/.368/.556/.924 with 37 HR when he was 35 to hitting .263/.334/.453/.787 with 22 HR the next year. Then Willie showed his greatness after that. With his power diminished - it was pretty much below .500 for the rest of his career - he switched to taking more and more walks and started stealing more bases: his OBP from that season was .334, .372, .362, .390, .425, .400, .303 at age 42; and he stole 23 bases at age 40, the most he had stolen in a season since he was 29 and stole 25 bases. That shows he wasn't kidding when he said that had he known that people would make such a big deal about 30-30 (HR/SB), he would have stolen that many more bases. Here he was, 42 years old and he still had enough speed (plus a lot of savvy) to steal 23 bases.
The only silver lining for Bonds is that from all indications, he has not been playing at 100% all season, that he has been gradually getting better physically and starting to make plays he couldn't before. However, this improved physical condition has not shown up yet in his batting stats.
One other possible silver lining is his BABIP is very low, at .227 this season. This is abnormally low for most batters, most tend to bounce around the mean of .300. However, if I remember right, when a hitter nears the end, his mean goes down. Another plus is his contact rate is still at a strong 85%. Together, this could mean that it was just one of those years for a hitter, where the fielders are just getting to the balls, which results in the lower BABIP and BA. However, last year, while true, it's small sampling because of so few ABs, his BABIP was almost identical at .226, which means that this season is a continuation of his problems hitting the balls for hits that he was having last season, as brief as it was.