Runs A Plenty
One of the basic truisms of a baseball season is that offensive levels are lower at the start of the season than they will be in the middle. Cold weather in April is the most accepted reason for why it takes a few months for offensive levels to normalize, and you can look back at pretty much any season and find that pitchers have an early season advantage over hitters.
This year, however, that doesn’t seem to be the case. MLB is averaging 4.96 runs per game so far in 2009, up from a league average 4.65 runs per game in 2008. It’s pretty rare to see run scoring in April higher than the league average from the previous season.
The main culprit appears to be a rise in home run rate. Last April, there was ahome run hit every 43 plate appearances. That number ended the season at one per 38 PA, as the ball flew better in warmer weather. So far this year, we’re at one home run per 34 plate appearances, accounting for 311 total home runs to date. At last year’s pace, we’d only have 248 home runs.
According to Greg Rybarczyk, who runs Hit Tracker Online, it isn’t just the number of home runs being hit either – the home runs are flying further than they used to, by an average of 8.5 feet per home run. Even with a limited sample, the probability of a deviation of that kind of distance is extremely unlikely to be caused by random chance.
After seeing run scoring levels decrease the last few years, we might be in for a spike in 2009. It’s worth monitoring, at least.
Dave is the Managing Editor of FanGraphs.
it might be that more games have been played at warmer sites relative to previous years. I believe the North east teams opened on the road and the west coast has been unseasonably warm.
The northern part of the west coast has not been unseasonably warm at all. In Seattle we had snow just a couple of weeks ago, and it’s been unseasonably cold for the entire spring.
That said, the Mariners opened on the road (though it didn’t look especially warm in Oakland either).