Why (other than tradition) is the minimum baseball center field
distance longer than the minimum foul line distance when most balls
are hit right or left of center? Is it possible that the distorted
shape comes from downtown stadiums being built in assemblages of
rectangular city blocks? Low price, I know, but 5* rating will be
given instantly!
(from http://www.aluminumbats.com/baseball_diamond.htm ): Any Playing
Field constructed by a professional club after June 1, 1958, shall
provide a minimum distance of 325 feet from home base to the nearest
fence, stand or other obstruction on the right and left field foul
lines, and a minimum distance of 400 feet to the center field fence.

Thanks for asking this question, I enjoyed the places the search took
me....

I tried pretty hard to find an specific online reference for this, and
couldn't, but I'm pretty sure the answer is just that it's easier to
hit a ball to center field (or near center field, in the "power
alleys", than it is to hit the ball down the line.)

There are a lot of 380-foot outs to the center part of the field, and
relatively few home runs hit more than 50 feet over the fence down the
foul lines, so my guess is that if the fences were, say, at a constant
distance of 360 feet, players would have a much easier time hitting a
home run to center field and might, perhaps, concentrate completely on
hitting the ball straight down the middle.

So I think the point is that making the middle of the field deeper
effectively makes it closer to "equally hard" to hit a home run in
various directions, which makes the game more interesting.

Here's an article about Detroit's new stadium that talks about the
field dimensions and their effect on the game:
http://www.detnews.com/2000/tigers/0005/09/f05-49662.htm

There have been many other ballparks where the field dimensions
affected the game, Fenway park being the obvious example that's still
in use: http://www.boston.com/allstar99/fenway/quirks.htm

searches tried: "power alley center field" "baseball outfield fence
design" "home run distance left right center" but none of them worked
all that well.

I was surprised I couldn't find a web page discussing this specific
issue, but I hope you feel I've given you your $2 worth.

Thanks,
David

Super work, very pleased!

Here's something else to consider, even though this has already been
sufficiently answered by someone else: physics.

When a pitcher delivers the ball to the plate, it is coming
(typically) along a line that extends from the center field wall (or
very close to, depending on where the pitcher aims).  That said, the
maximum transfer of power occurs when the batter makes contact with
the ball in such a way that it will travel directly back over the
pitcher's head and sail towards straignt-away center field (the
mid-point of his swing).  If the batter makes contact before or after
the mid-point, maximum power transfer will not occur and the ball will
not travel as far as it could have.  Thus, the center field fence
would need to be longer than the others to try and take away some of
the effects of physics when it comes to slamming home runs.

Batters who can consistently hit the ball over the center field fence
have an awesome ability to calculate quickly how fast the ball is
travelling and it's exact location such to make contact at the
mid-point of his swing and transfer maximum power.  Batters who can
consistently crush the ball over any other part of the fence have
enough raw power in their swing to get it over without making contact
at the mid-point.  Either way, both kinds of batters should be admired
for what they can do.