Major League Baseball is mulling a number of scenarios for the 2013 schedule that will bring dramatic change to Interleague Play and could result in fewer games between intracity rivals such as the Mets and Yankees.
The move of the Houston Astros from the NL Central to the AL West beginning next season will give each league 15 teams, divided into three divisions of five teams each. Such an alignment will mean that an Interleague game must be played virtually every day during the regular season, thus ending the present Interleague period that begins each year in May and ends in June.
An MLB spokesman cautioned, though, that "nothing is finalized." MLB must submit a tentative schedule to the MLB Players Association for approval by July 1.
In one potential change, it's possible that in addition to the Mets and Yankees, other natural rivals such as the Angels and Dodgers, Cubs and White Sox, Giants and A's, Royals and Cardinals, and Orioles and Nationals might not play each other the accustomed six times every season. Instead, they would play each other six times every three seasons as the Interleague schedule rotates between divisions.
The schedule change would also mean fewer games between non-regional Interleague matchups, such as the Padres and Mariners, except in years when their divisions were assigned to each other.
In the years in between, the schedule would feature three or four games between those teams.
Under any new format, the Astros and Rangers will face each other 18 times a year because they will play in the same division.
Interleague play began in 1997. A year later, MLB added two teams -- Arizona to the NL and Tampa Bay to the AL -- and the Brewers moved to the NL, giving that league 16 teams to avoid the Interleague game-a-day scenario. But as part of last year's collective bargaining for what turned out to be a new five-year Basic Agreement, the union insisted on the 15-15 competitive balance split in exchange for expansion of the postseason.
As a result of those negotiations, each league has added a second Wild Card team and a one-game playoff to the existing playoff format, beginning this postseason.
Barry M. Bloom is a national reporter for MLB.com and writes an MLBlog, Boomskie on Baseball. Follow @boomskie on Twitter. This story was not subject to the approval of Major League Baseball or its clubs.