Making the Most of Fenway Park

How will J.D. Drew perform in Fenway (that is, if he ever actually becomes a member of the Red Sox)? That is the question some Red Sox fans attempted to answer recently over at the Sons of Sam Horn Red Sox forum. It's not an easy question to answer, of course, but given the wealth of available information on batted ball locations, we can at least start looking at these things.

First of all, let's temper our expectations right from the start. Trying to project a player's performance into a different setting is exceedingly complicated, and some might consider it a fool's errand. The depth and height of the outfield fences is just one way a park might affect a particular hitter. There are many other ballpark characteristics that can affect different players in different ways: the hitting background, the amount of foul territory and the length of the infield grass, to name just three. And this doesn't even address effects not associated with the park itself: the aggressiveness of the fan base and press corps, for example, or the quality of a city's nightspots. I have often wondered if Mickey Mantle might have been even greater than he was had he played in some peaceful Midwestern town instead of under the bright lights of the City that Never Sleeps.

Staying Within Our Game

So, let's just take a baby step: Let's try to figure out how Fenway Park's most characteristic feature, the short, high, fence in left field, known to everybody as the Green Monster, affects different players. Here's a picture of the Monster, taken during the 1999 All-Star game: note that there were no Green Monster seats back then, so you can clearly see the screen that used to keep home run balls from crashing down onto Landsdowne Street, just behind the wall. Many a famous home run ball has come to rest in the screen — from Pudge's immortal Game 6 shot-heard-round-New England to F'in Bucky's devastating three-run chip shot in October 1978.

As everybody knows, the distance down the left field line in Fenway is short: 310 feet, to be precise. Not only that, but the wall cuts straight across left field (the wall is parallel to the right field foul line) without angling back as most outfield fences do. That means that a fair amount of territory that is within the field of play in most left fields is beyond the wall in Fenway. Of course, the wall is much higher than most outfield fences, which makes it harder to hit the ball over it.

The best way to get a handle on how the Wall influences play is to look at hit charts of balls hit in the Wall's vicinity. Here is such a chart for batted balls hit near the Green Monster during the 2005 season and, for comparison's sake, balls hit to the same area in Yankee Stadium. These charts have a lot going on, so let's take it one step at a time.

First, the black outlines correspond to a generic ballpark that is 325 feet down the lines and 405 feet to dead center. The green line represents the position of the Green Monster in Fenway Park. Each colored point represents a ball hit in the air: either a fly ball or a line drive. The position of each point shows where the ball was fielded. Here, let me emphasize this important point:

• The points do not indicate where the ball landed, but rather where it was fielded.

The color of each point gives the outcome: either some kind of hit or an out. For the Fenway chart, you can clearly see that the home runs are going over the wall and that most of the balls fielded in front of the wall are doubles and singles. Presumably, many of those balls hit up on the wall somewhere and were fielded when they came back down. Comparing the two hit charts, it's very clear that quite a number of Fenway home runs would have been either outs or doubles in Yankee Stadium. Note that the black outlines have nothing to do with the true dimensions of Yankee Stadium. I do not have the measurements necessary to make an accurate drawing of the different ballparks, so I just use the generic outlines for illustrative purposes.

If you look carefully at the hit locations in Fenway, you'll probably spot a problem: as you move towards center field there are fewer balls fielded near the base of the wall. At first I thought my positioning of the Green Monster might be incorrect. I came up with the dimensions using the satellite photography available on Google Earth. I believe the MLB scorers who record the hit locations use the drawing of Fenway Park that you see in their Gameday application or in their hit charts. Here is a comparison of the two versions of Fenway:

Google Earth Image	MLB Drawing

The Wallbangers

How did the 2005 Red Sox exploit the Wall? (I restrict myself to 2005, since that is the only year for which I currently have data.) One way to answer this question is to total up, for each player, the number of times that a) a home run landed within 30 feet of the wall, or b) a hit was fielded within 25 feet of the wall. The idea is that these are balls that often would be outs in other parks, but are either home runs or doubles (or singles) in Fenway Park.

An important point must be made here: when a ball hits off the Green Monster it is typically fielded near the base of the wall, although sometimes the rebound is substantial. That is why I consider any ball fielded within 25 feet of the wall to be a possible wall-ball. Of course, many balls are fielded near the base of the wall without having bounced off it—plenty of balls go down the line, in the left-center field gap or simply get by the left fielder and end up rolling to the wall.

I do not know what fraction of balls fielded near the wall's base actually hit off the wall. To get some feel for this, I viewed video of 27 wall-ball candidates hit by Kevin Millar, Bill Mueller, David Ortiz and Doug Mirabelli. Of those 27 balls, 17 actually hit the wall, or 63%.

Ninety percent of Millar's balls actually hit the wall on the fly, while only 25% of Mueller's did. The difference should not be too surprising: Millar is a dead-pull, fly ball hitter with decent power. Most of his wall-balls were high drives produced by an extreme upper-cut swing. Mueller, in contrast, is more of a line-drive gap hitter and most of his wall-ball candidates were either in the left-center gap or else down the left-field line (especially when the switching-hitting Mueller was batting left-handed).

Of course, this is a small sample, so I don't really know how many of the wall-ball candidates overall actually hit the wall on the fly. I think 50% might be a reasonable guess: I believe my 63% number is a bit high because three of the four players I looked at had above-average power.

So here is the table of short home runs (landed within 30 feet of the wall) and wall-ball candidates (doubles and singles that were fielded near the base of the wall):

+------------------+----+------+------+------+------+
| Name             | H  | 1B   | 2B   | 3B   | HR   |
+------------------+----+------+------+------+------+
| Millar, Kevin    | 18 |    5 |    5 |    0 |    8 |
| Ramirez, Manny   | 14 |    5 |    1 |    0 |    8 |
| Ortiz, David     |  9 |    1 |    4 |    0 |    4 |
| Mueller, Bill    |  9 |    2 |    6 |    0 |    1 |
| Mirabelli, Doug  |  6 |    1 |    3 |    0 |    2 |
| Renteria, Edgar  |  6 |    0 |    5 |    0 |    1 |
| Nixon, Trot      |  5 |    1 |    4 |    0 |    0 |
| Varitek, Jason   |  5 |    0 |    4 |    0 |    1 |
| Graffanino, Tony |  5 |    0 |    3 |    0 |    2 |
| Damon, Johnny    |  4 |    0 |    4 |    0 |    0 |
| Bellhorn, Mark   |  3 |    0 |    2 |    0 |    1 |
| Olerud, John     |  3 |    2 |    1 |    0 |    0 |
| Kapler, Gabe     |  2 |    0 |    2 |    0 |    0 |
| Hyzdu, Adam      |  1 |    1 |    0 |    0 |    0 |
| Vazquez, Ramon   |  1 |    1 |    0 |    0 |    0 |
+------------------+----+------+------+------+------+

Boston's premier right-handed slugger, Manny Ramirez, also made good use of the Green Monster, with eight short home runs over it and six wall-ball candidates. Here's something interesting: of Manny's six wall-balls only one went for a double. Good hustle, dude! Oh, well, that's just Manny being ... lazy.

Lefty slugger David Ortiz and Bill Mueller each had nine balls where the Wall potentially came into play. However, while Mueller actually didn't benefit much from the Wall (in 2005), as we saw above, Ortiz did: in addition to the four home runs, Ortiz banged another three off the wall.

Backup catcher Doug Mirabelli also did an admirable job of exploiting the Monster in 2005, hitting the wall three times and clearing it twice in just 152 plate appearances. He also hit much better at Fenway than on the road that year, to the tune of about 250 points of OPS.

Lefty or Righty? Conventional Wisdom is Right!

Conventional wisdom, that guy that I love to prove wrong, has it that the Sox should stock up on right-handed power hitters to fully exploit the Wall. But one of the things that I've learned since poking around with baseball statistics is that fly balls are preferentially hit to the opposite field, i.e., left-handed batters hit more fly balls to left field than to right and vice versa for right-handed batters. So, maybe you want a left-handed hitter with decent power who can loft those fly balls over the Monster? Somebody like J.D. Drew, maybe?

Well, before we start looking at the data, there are a couple of things to keep in mind: it's true that a majority of fly balls hit by left-handed batters go to left-of-center, but it's a small majority, 54% to be precise. And if you restrict yourself to home run fly balls, the vast majority of those are pulled, not hit the opposite way. Furthermore, Fenway Park is quite deep in right field and overall, Fenway significantly supresses home runs for left-handed batters. Indeed, David Ortiz hits more home runs on the road than he does at home.

Ok, with those ideas in mind, here are the Red Sox wallbangers, broken out by handedness:

Batting Left-Handed
+----------------+---+------+------+------+------+
| Name           | N | 1B   | 2B   | 3B   | HR   |
+----------------+---+------+------+------+------+
| Ortiz, David   | 9 |    1 |    4 |    0 |    4 |
| Nixon, Trot    | 5 |    1 |    4 |    0 |    0 |
| Mueller, Bill  | 4 |    0 |    4 |    0 |    0 |
| Damon, Johnny  | 4 |    0 |    4 |    0 |    0 |
| Olerud, John   | 3 |    2 |    1 |    0 |    0 |
| Varitek, Jason | 3 |    0 |    3 |    0 |    0 |
| Bellhorn, Mark | 1 |    0 |    1 |    0 |    0 |
| Vazquez, Ramon | 1 |    1 |    0 |    0 |    0 |
+----------------+---+------+------+------+------+
Batting Right-Handed
+------------------+----+------+------+------+------+
| Name             | N  | 1B   | 2B   | 3B   | HR   |
+------------------+----+------+------+------+------+
| Millar, Kevin    | 18 |    5 |    5 |    0 |    8 |
| Ramirez, Manny   | 14 |    5 |    1 |    0 |    8 |
| Renteria, Edgar  |  6 |    0 |    5 |    0 |    1 |
| Mirabelli, Doug  |  6 |    1 |    3 |    0 |    2 |
| Mueller, Bill    |  5 |    2 |    2 |    0 |    1 |
| Graffanino, Tony |  5 |    0 |    3 |    0 |    2 |
| Kapler, Gabe     |  2 |    0 |    2 |    0 |    0 |
| Bellhorn, Mark   |  2 |    0 |    1 |    0 |    1 |
| Varitek, Jason   |  2 |    0 |    1 |    0 |    1 |
| Hyzdu, Adam      |  1 |    1 |    0 |    0 |    0 |
+------------------+----+------+------+------+------+

Next Up — Out of Towners

I suppose many Red Sox fans will read this article and say, "Well, duh!" They know that Ortiz and Ramirez and, especially, Millar have put the Green Monster to good use. Of course, it's nice when the data support our perceptions, plus I like to make those plots with the colored dots and stuff.

Next time I hope to uncover something interesting about players on other teams and how they might be expected to perform at Fenway, at least as regards the Green Monster. Stay tuned.