UPDATE 08.25.09: This post is a little outdated. An up to date, less confusing (I hope), and more accurate (I hope again) explanation can be found here.

With the Tigers venturing into uncharted territories, Detroit fans are probably a little confused on how playoff rosters work. Even if you weren’t confused, you probably will be after this explanation.

The first rule seems simple and straight forward enough:

According to Rule 40(a), a player must be on his club’s active big league roster or disabled list (or bereavement list, suspended list, or military list) on August 31 in order to be eligible for post-season play.

But does anybody remember the 2002 playoffs where Francisco Rodriguez was on the playoff roster despite being in the minors on August 31st? In fact Rodriguez didn’t pitch in the majors until September 18th that year. If a team has a player on the disabled list, they can be replaced. Now depending on where you look, this rule can vary. One variation says that this exception is only for the 60 day DL, and the eligible player can be anyone in the organization. Jim Callis from Baseball America doesn’t specify the DL type, but that the player must be on the 40 man roster.

The only real catch is that the replacement player must play the same position, like a catcher for a catcher, and infielder for an infielder, etc.

Much of the confusion comes from the fact that the rule isn’t really publicized with other Major League rules. The cleanest and simplest expanation I’ve come across is at Mike’s Baseball Rants:

Playoff Rosters: Playoff rosters must be set at 25, not including disabled players, on August 31. For each player on the 60-day DL, teams may add players to the eligible list during the playoffs at the same position, provided that they were in the orginization on August 31… Teams must choose 25 players from their playoff eligible list before each round of the playoffs.

As for what it might mean for the Tigers, they currently have 2 pitchers on the 60 day DL in Craig Dingman and Troy Percival (Mike Maroth is also, but he will most assuredly be activated regardless). So the Tigers could make 2 more players eligible, as long as they were pitchers. If they were to exercise this option Jordan Tata or Chris Spurling could be possibilities – albeit longshots.

As for position player possibilities, as I covered yesterday the Tigers could recall and then DL Tony Giarratano meaning that another infielder such as Chris Shelton could be added. The only hit for the Tigers is that they would incur a month of service time for Giarratano, which I don’t see having any significant ramifications.