Fantasy impact of Astros' move to AL

Brace yourselves, fantasy baseball veterans. Following the upcoming 2012 season, we're going to see our first franchise league switch in 15 years, and only the second since the American and National Leagues formed one major league in 1903.

Beginning with the 2013 season, the Houston Astros will switch from the National to American League, giving each major league an identical 15 teams.

Those of you in AL- or NL-only keeper leagues might be familiar with the impact of a player switching leagues, but it's rare that a franchise does it. Ubaldo Jimenez's NL-only owners this past summer can attest; those who played in leagues that do not allow a player's statistics to be carried over when he switches leagues simply lost Jimenez with no compensation in return.

Now league commissioners have to decide what to do when an entire team does it.

What's fortunate about the news is that of the 30 franchises, the Astros' current roster -- from an individual player perspective -- might represent the one with the least wide-reaching impact of a league switch, at least in those keeper leagues where the current rule set requires those players be forfeited.

Counting only currently contracted Astros players, Carlos Lee ranked highest on our 2011 Player Rater, but he finished 120th, the lowest mark for any team's leader. Only three Astros finished among the top 250 (the number of regular, non-DL roster spots in an ESPN standard league): Lee, Mark Melancon (151st) and Wandy Rodriguez (187th). Narrowing the scope to only the NL-only player pool, Lee finished 59th and those aforementioned three were the only Astros to crack the top 100, and only 10 Astros players finished in the top 250, the fewest of any National League team (Cincinnati Reds and Pittsburgh Pirates each had 13).

In an NL-only keeper league, the obvious answer might be to afford the owner of Astros players to void any long-standing contract on that player upon the conclusion of the 2012 season. Make no mistake: Commissioner's discretion becomes important, and such rulings need be made in advance of the 2012 campaign, while there is plenty of time for those affected owners to prepare.

As for how the Astros' departure impacts the structure of NL-only leagues, it's simple mathematics: There will be 25 fewer active players in the talent pool at any given time beginning in 2013. In 13-team NL-only leagues, such as long-standing "experts" leagues like the League of Alternative Baseball Reality (LABR) or Tout Wars, filling back-end roster spots will become slightly more challenging. We'll see how such leagues will choose to adapt -- if at all -- but it's possible some leagues might shed roster spots, or perhaps even a team entirely.

Conversely, AL-only leagues, which had suffered through a thinner, 350-man player pool -- 14 teams times 25 active roster spots -- for so many years, now get 25 additional active players from which to choose. Whereas NL-only leagues might aim to shed roster spots, AL-only leagues might opt to add a few, or perhaps an entire extra team. Perhaps we'll see all AL- and NL-only leagues become 13-team, 23-active player (14 hitters, nine pitchers) identical formats … which makes sense because the two major leagues would also be identical.

But besides the lost roster spots, it's actually the impact upon the American League that's more significant to fantasy owners.

First off, two 15-team major leagues will require interleague play on a daily basis, meaning in any given season there must be a minimum of 162 interleague games on the schedule. While Major League Baseball's scheduling plans haven't yet been released, a schedule that includes 72 games (18 apiece) against division opponents, 60 (six apiece) against teams in the league's other two divisions and 30 interleague games makes sense. That's nearly twice as much interleague play as we have currently, and it'll no longer be confined to a mere weekend in May and two-plus weeks in June/July. The age-old "to designated hitter or not to designated hitter" question will crop up more often, presenting more difficult lineup decisions. Designated hitters, as a whole, stand to lose value.

Look at it this way: This past season, David Ortiz and his Boston Red Sox played nine games at National League parks, where they lacked the designated hitter, and they did so in consecutive series from June 24-July 3. Under a 30-game interleague schedule, he would play 15 in NL parks but scattered all over the calendar, so it wouldn't be as easy to adapt as if you had owned him in 2011, when it was clear you should've simply benched him for the entire June 27-July 3 week.

Another factor is that by bringing Houston's Minute Maid Park to the AL, we might add yet another hitter-friendly venue to the DH league. Sure, Minute Maid Park leaned in favor of pitchers in terms of runs in two of the past three seasons (2009 and 2010), but it has long favored hitters in terms of home runs and was once known as one of the most hitting-friendly ballparks in baseball, back when the Astros were perennial contenders. A thought: Might it be that the talent -- or lack thereof -- is partly responsible for the statistical leaning toward pitchers? It's a guess, but my hunch is that Minute Maid will rank among the top 10 hitters' parks in both runs and home runs in 2013, and will be again classified as hitter-friendly.

As for the individual Astros players, remember that this is a franchise in transition, only beginning a probable multiyear rebuilding plan. Two of the most recognizable Astros players in fantasy, Lee and Rodriguez, might not even be with the team come 2013. Certainly Lee's odds are poor; his contract expires next winter.

Rodriguez remains signed through 2013, and he might be the most individually affected player. In 22 career interleague starts, he's 8-10 with a 5.25 ERA and 1.42 WHIP, and in the 12 of those starts that occurred since he became a household name in fantasy in 2008, both his ERA (5.64) and WHIP (1.49) were actually worse. His triple-slash statistics (AVG/OBP/SLG) allowed, since 2008, were also noticeably lower against NL Central competition (.246/.303/.384) than against all other teams (.257/.330/.410). Certainly, his competition will increase in difficulty.

Younger Astros pitchers might struggle to quickly transition to the major leagues, or to sustain success over the long season. Bud Norris, now 26 years old with two-plus years' experience, could suffer in the ratio categories, and Jordan Lyles (21), Brett Oberholtzer (22) and Jarred Cosart (21) will face steeper challenges initially, even if only because of the presence of the DH on a near-nightly basis.

That's well worth keeping in mind come draft day 2012 in keeper leagues. One thing is for certain: Any rules set to address this change should be made in advance of that date, and you'll want to make sure you've digested them fully beforehand.

Tristan H. Cockcroft is a fantasy baseball analyst for ESPN.com and a two-time champion of the League of Alternative Baseball Reality (LABR) experts league. You can e-mail him here, or follow him on Twitter @SultanofStat.