Much has been made of the bipolar nature of Wrigley Field. It’s short in the power alleys but long down the lines. When the wind’s blowing out, it’s a home-run haven, a place for memorable slugfests. Reverse the wind, and we see a lot of warning-track outs.
It caught my attention on a recent Cubs broadcast when it was said that last year, Wrigley Field favored pitchers. Imagine that, the site of the memorable 10-homer, 23-22 loss to the Phillies in 1979 being a pitchers’ park.
In terms of home runs, Wrigley did favor pitchers overall. The wind in vs. wind out days balanced in favor of wind in. Wrigley Field had a home-run park factor of 0.962, meaning the Cubs and their opponents hit only 96.2 percent as many home runs at Wrigley as they did in Cubs road games. It was the second consecutive year the ballpark depressed home runs, with a park factor of 0.987. In the last 10 years, that has happened one more time, 0.975 in 2003.
But there’s more to offense than home runs and more to park effects than the wind. Wrigley Field has a great hitter’s background, with the center-field bleachers off-limits to fans, and it has small foul territory. The short distance from foul line to stands means more balls are fouled out of play and get more second chances for hitters.
The bottom line is that even in years when Wrigley has a below-average park factor in home runs, it’s usually above average in scoring. The runs park factor at Wrigley has been above break-even in nine of the last 10 years, including two of the three in which it was a below-average home-run park.
Last year, the runs park factor was 1.024, and in 2003 it was 1.061, meaning it was an above-average scoring park in two of the three years it was on the down side in home runs.
The exception was 2011, and that was an odd little year. The Cubs and their opponents scored only 93.4 percent as many runs at Wrigley as on the road. The park factor for doubles was 0.858, extraordinarily low in a park that has increased doubles in eight of the last 10 years, but triples rose to 1.321.
The same year also was odd on the South Side, with a runs park factor of 0.991. It was one of only two in the last 10 in which Sox and their opponents scored less often at U.S. Cellular Field than at other ballparks. But U.S. Cellular has been a great power park, including a home-run factor of 1.349 last season.
The home-run factor has been above break-even every season in the last 10, with none lower than the 1.193 of 2009 and ranging up to 1.545 in 2010.
Year in and year out, both ballparks are better-than-average places to score runs. How they get there is different, with U.S. Cellular not so bipolar in its home-run nature.