Hooray For Spring!!! Featuring Part II of the "Coors Field Effect"

Hello dear readers! It is I, The Beard, enjoying another spring in Arizona! I must say, while I enjoy a nice quiet winter day on Earth as much as the next eternal entity, nothing beats spring, and spring sure comes early in Arizona. And speaking of "early in Arizona," the Rockies have looked pretty good so far. Cook and DLR have had impressive outings, and Jeff Francis' return to the mound, despite the expected hiccups, is encouraging. A good spring training doesn't always lead to a good season, but a good start to spring is better than a bad one.

This year, the Rockies find themselves in an unusual position: the favorite to win the NL West. While they prepare and get in shape this spring, I am also working out and getting trim (are you surprised, readers, that a time- and space-traveling Beard would have a sense of humor?) to be ready to help them take those steps towards greatness. I have much Beardly work to do in the next few weeks, and a few more days by the pool and watching baseball in the sun should have me just about ready to get to the job at hand. Until then, please enjoy the second of Year of the Beard's three-part series on the Coors Field Effect.

THE COORS FIELD EFFECT: PART II
Starring: 
The Colorado Rockies
The Humidor

and introducing "Duck-Hunting Boots" as The Staff of Ra

A Sad Pitcher... Get It?

For eight seasons, the Colorado Rockies struggled to put together a team that could win at Coors Field. Hitting was not a problem – the park was the most prolific offensive ballpark in MLB history – but even with the boost they got at home, the Rockies were not successful, as no matter how well they played at home, they displayed a curious inability to win on the road. The effect on Rockies pitching was disastrous, as the team’s ERA was miles behind the league average every year. Rockies’ management brought one star pitcher after another to Coors Field, with increasingly disappointing results. Many believed that the Rockies would never be competitive, and that the peculiarities of playing at such high altitude would forever reduce the Rockies to an interesting MLB sideshow. 

Denver’s high altitude and “thin air” were part of the problem, and the massive outfield designed to lessen the effects of altitude only helped to create even more offense and make things that much tougher for pitchers. Short of raising the fences, it was thought there was nothing that could be done: baseball at Coors Field would always be a mockery of the game, and the Rockies would always struggle to field a competitive team. However, there was a third factor lurking behind the scenes, and its discovery was in large part due to a cranky hunter whose boots did not fit.

The story goes that a Rockies employee, getting ready for the autumn duck hunting season, was irritated to find that his leather hunting boots no longer fit him. Somebody told him that this happened all the time, as Colorado's hot and dry summers cause leather clothing to shrink. This got him thinking, and he began to wonder if the same thing might happen to the leather on a baseball. So a pair of ill-fitting boots led to the discovery of the final (and ultimately, the crucial) aspect of the Coors Field effect: Colorado’s low humidity made the baseballs used at Coors Field drastically different than they should have been.

By comparing the baseballs being used at Coors Field to brand-new baseballs direct from the Rawlings factory in Missouri, it was learned that the balls at Coors Field were substantially smaller, harder, lighter, and slicker than standard baseballs. Some Coors Field baseballs weighed up to a full ounce less than the 5-5.25 ounce standard set by MLB. This was found to be a direct result of Denver’s very low humidity… Denver’s is classified as a semi-arid, or high-desert climate. Simply put, baseballs used at Coors field had dried out. The smaller size and weight, and the slickness of the dry leather, made it even more difficult for pitchers to grip and control their pitches, and the hardness and lighter weight of the ball made it jump off the bat faster and fly farther.

The extent of the role the ball itself plays in the game can be seen by examining the game’s history. Baseball fans and historians often break the history of baseball into two eras: the Dead-Ball and the Live-Ball Eras. Contrary to common belief, even though manufacturing standards continued to improve, no drastic change to the baseballs themselves marked the end of the Dead-Ball era... it was a rule change or two that did it.

Prior to 1920, it was common practice to use the same baseball for an entire game, often not replacing it until its seams actually began to unravel. Baseballs would absorb dozens, if not hundreds, of hits, and by mid-game were often dirty, scuffed-up, oblong, and mushy… all factors which helped pitchers and made things very difficult for hitters. Consequently, scoring was low, and home runs were scarce. 

Prior to and during the 1920 season, however, a number of rules were put in place to boost offense, including a rule that baseballs were to be continually replaced during the game as they showed signs of wear. Instead of swinging at dirty, lumpy, and soft baseballs which dipped and moved in unexpected ways, batters now had a consistent baseball to swing at on every pitch. The jump in offensive numbers was spectacular… In 1919, Babe Ruth set the record for home runs in a season with 29; in 1920, he nearly doubled his own record, with 54.

The difference between the pre-1920 and post-1920 game was so dramatic that an era of baseball’s history ended, and a new one began… and a major reason behind it was having a consistent baseball thrown on each pitch. The comparison between live-ball and dead-ball era baseballs is similar in many ways to the comparison between Coors Field baseballs and those used everywhere else… the Coors/live-era ball was harder, slicker, and easier-to-hit baseball that slipped out of pitchers hands and jumped off bats, leading to huge offensive numbers. When people half-jokingly said that playing baseball at Coors Field was like playing a different game altogether, they were very close to correct… it was the same game, but with a different baseball.

After much experimentation, the Rockies came up with a simple solution. In 2002, the team installed what became known as the “humidor,” in which to store all the baseballs delivered to the team throughout the year. The humidor allows the team to control the temperature and humidity at which the baseballs are stored, right up to game time.

The change was sudden and dramatic – runs, hits, and home runs at Coors Field fell drastically as soon as the humidor was put in use. Runs scored at Coors Field dropped more than a run per game, from 13.40 in 2001 to 12.21 in 2002. Home runs fell nearly half per game, from 3.31 to 2.86, and the Rockies’ home batting average dropped from .331 to .316. As the Rockies perfected the use of the humidor (and as their roster, particularly their pitching staff, improved), these numbers have continued to drop.

The result of the humidor is this: Coors Field is no longer the absurdly prolific offensive ballpark that it was from 1995-2001. The effect of high altitude on both batted and pitched balls did not change, nor did the dimensions of the field, but after the humidor was installed, Rockies fans began to see something they had rarely witnessed: low-scoring, well-pitched games. There have been eight 1-0 games pitched in the history of the Coors Field. Not coincidentally, all eight games took place after introduction of the humidor. (see note below)

There is no doubt that even with the humidor, Coors Field remains a strong hitters’ park. However, it is no longer ridiculously more so than the rest of the league. Looking at the park factor ratings (the number designed to show whether each individual park favors hitters or pitchers over a number of categories) since 2002, we can see that Coors Field -- while still a hitter-friendly park by any definition -- is no more so than half a dozen other parks in the league. Over the last five seasons, in runs scored, Coors ranked 2^nd, 2^nd, 3^rd, 3^rd, and 1^st… high rankings to be sure, but only once in the last five years was it the highest-scoring park in the league. In home runs (Coors Field’s middle name), the park has ranked: 9^th, 10^th, 5^th, 3^rd, and 9^th... by no stretch of the imagination the numbers you'd expect from an extreme home run park.

Is Coors Field a good place to hit? Without question, it is a very good place to be a hitter, and still not a great place to be a pitcher… but every statistic shows that “Coors Canaveral" -- a venue unmatched as a warper of offensive statistics -- died in 2002. Today, any number of ballparks are equally good hitter's parks, yet lazy sports reporters and uninformed fans continue to view Coors Field as they did in its early years: as if it was light years beyond any other park in the majors. A bias still exists against the park and those who play there, with the ability and accomplishments Rockies hitters largely discounted (oddly, Rockies pitchers rarely receive the inverse, a bump in their perceived value for succeeding in spite of the CFE). Great Rockies and ex-Rockies such as Helton, Holliday, and Walker continue to be viewed through the distorting lens of the Coors Field Effect.

In Part III of The Coors Field Effect, we will examine the effect that the home park's reputation -- both pre- and post-humidor -- has on both Rockies hitters and pitchers. Is there a fair method of comparing Rockies players to their peers, and will the best players in Rockies history get a fair shot at the Baseball Hall of Fame?

NEXT: The Reputation: Deserved or Unfair?

(note) The only no-hitter ever pitched at Coors Field, by Hideo Nomo of the LA Dodgers, was well before the humidor, in 1996. In fact, that no-no was pitched against one of the all-time greatest Blake Street Bombers lineups (three Rockies hit 40+ HRs that season). This would seem to conflict with the notion that a low-scoring game was impossible at Coors, but there is one major factor in that particular game which is only hinted at in the box score: it was a cold, wet September night, and the game had been delayed by almost two hours to rain, which continued to fall throughout the early part of the game. Knowing how heat and humidity affect the baseballs at Coors, the weather conditions that night were certainly a factor for Nomo's no-hitter. It would be interesting to know about the balls used for that game: had they been stored at Coors Field for weeks or months, or had a new shipment just arrived? In any case, even considering the weather, Nomo's no-hitter at Coors during its offensive-output heyday was an astounding feat, and should probably be even more highly-regarded than it is today.