Over the past weekend, the White Sox signed free agent catcher Toby Hall. With all the free agent madness this offseason, this signing probably looked insignificant. However, our analysis shows White Sox GM Ken Williams might have hit that GM sweet spot.

At first glance, the White Sox catcher position provided about average offense. They were #17 of 30 teams in On-base percentage Plus Slugging percentage (OPS).

However, catchers take a beating during the year and that makes it the best position for a platoon. In the last five seasons, no catcher has caught more than 147 games in any single year.

Which leads us to this question: How did the White Sox catchers do against pitchers based on handedness? Here are the top and bottom five teams in catcher OPS vs right-handers:

Well, the White Sox and primarily A.J. Pierzynski did quite well against RHP. No need to make any change here.

Let’s look at the other side. How did the White Sox catchers do against lefties? Here are the top and bottom five teams in catcher OPS vs left-handers:

Wow, now we found a glaring weakness. The White Sox catchers were terrible against left-handed pitchers. Even worse, the opponents like using lefties against the White Sox. 40% of the starters facing the Sox last year were lefties—a five-year high for the White Sox. Obviously signing Jim Thome before the season dictated opponent strategies.

Does Toby Hall fit the need?

Based on the 2006 season, this seems like the perfect fit. If Hall had been with the Sox in 2006 and did the same thing against lefties instead of the what the White Sox actually got, the Sox would have come in 4th, instead of 17th, in catcher offense for the season among the 30 MLB teams.

One year may be a fluke. However, the three-year numbers, while not quite as strong as 2006, still suggest a very effective platoon for 2006.