Rios in the Cell

Alex Rios was claimed off of waivers today and will be a Chicago White Sock shortly. In our look at Scott Rolen and Nick Johnson in their new digs, we established somewhat of a precedent for trying to analyze the effect of a mid-season home park change: look at the park left behind, the new park, and the tendencies of the hitter as well as their history. So let’s take a look at Rios from an offensive standpoint, as the White Sox ponder their $60 million dollar addition.

The team has had historic problems in center field, so in some ways they can’t be blamed for coveting a player that has performed well in center field (12.8 UZR/150). But let this be about his offense, which has been inconsistent at best.

At first glance, his power shouldn’t be too effected by the move. Rogers Centre currently has a 1.152 park factor for home runs, and US Cellular a 1.164 number. However, Rogers had a sub-1.00 park factor for home runs last year, another park pointing at the instability of park factors. Over a three year period, Rogers came in at a 1.20 park factor while the Cell had a slightly more robust 1.293 park factor for home runs.

So far we’re looking at a maximum of a 5% overall power increase for Rios. Like with Rolen and Johnson before, 5% on a player averaging around 20 home runs a year is not a huge increase. Could Rios profile well for US Cellular and receive more of a power boost?

Though I still desire more detailed spray charts for hitters – and would appreciate being put in the right direction by anybody reading this piece – www.hittrackeronline.com can give us his spray charts for home runs.

Rios pulls almost all of his home runs. He’s hit 10 of his 14 this year to left field, as his home run chart shows. This continues a trend – last year he hit 14 of 15 out in left field, and the other was in left-center. 20 of his 24 in 2007 went out to left or left-center.

The Rogers Centre is 328 down the line and 375 in the left-center power alley. US Cellular is 330 down the line and 375 in left-center according to wikipedia. Perhaps it’s the wind that helps the Cell play tougher on pitchers, because the dimensions are practically the same.

The final question, it seems, is if Rios will ever bust out with some real power. A popular answer has been that he won’t because he hits too few fly balls. But his career fly ball rate (37.2%) is weighed down by his first two years in the league when he was a true worm-burner. He’s settled in around 40% now, and there are plenty of other sluggers that hit 40% of their balls in the air (Adrian Gonzalez and Lance Berkman just to name a couple).

What those other sluggers have that Rios doesn’t just happens to show up in their respective home runs per fly ball numbers. Rios (9.5% this year, 8.6% career) just doesn’t measure up to Gonzalez (17.3% career) and Berkman (19.6%). After 3071 plate appearances and a home run per fly ball rate just around the league average, I think it’s safe to say that Rios, in his average season, will display 20-home run power, no matter which of these two fields he calls home.