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The National League is often referred to as the "senior circuit," so called because it is the older of the two leagues that make up Major League Baseball. The National League was officially formed in 1876. The American League came into existence 25 years later, in 1901, rendering the AL the junior of the two professional leagues.
The NL might be the older of the two leagues, but it arguably hasn't been where Major League Baseball's power center rests for the better part of the past two decades. The Major League All-Star Game, which annually features the best - or at least the most popular - players in both the National and American Leagues in a midsummer exhibition game against each other, has been dominated in recent years by the American League All-Stars.
The AL All-Star squad has won 15 of the past 20 games. Despite their improbable run of success in the All-Star game, however, the American League team has won only two of the past six World Series. MLB historians say the introduction of the designated hitter in 1973 forever changed the balance of power between the two leagues, providing the American League with an additional offensive weapon that replaced the pitcher in the batting order.
The designated-hitter rule only applies to the American League. The National League never adopted the DH. As a result, good hitters in the NL who have may have become a liability in the field because of their age and loss of agility, can extend their careers by taking on a designated-hitter role with a team in the other league.
Something else that the American League will have that the National League doesn't, starting in the 2013, is the Houston Astros. After 51 years in Major League Baseball, all of it in the National League, the team that began in 1962 as the Houston Colt .45s will move next season to the American League, where the Astros will become the fifth team in the AL West. That move will balance out both leagues at three divisions of five teams each, resulting in two leagues of 15 teams each.
When Houston moves over to the American League joining the Texas Rangers in the AL West, it will be the first time since 1997, the year before the last baseball expansion, that both leagues have had the same number of teams. After the 1998 MLB expansion, which brought about the then Tampa Bay Devil Rays and the Arizona Diamondbacks, the American League consisted of 14 teams and there were 16 in the National League.
Considering where the Astros are likely to end up in their National League farewell season, they probably will welcome the relocation and change of environment. Houston will start out the year at the bottom of the 16-team National League in our 2012 Preseason Power Rankings for the senior circuit. Read on to find out where the other 15 teams fall.
2012 Preseason National League Power Rankings
1. Philadelphia Phillies - The best pitching rotation in baseball will propel the Phils again in 2012.
2. St, Louis Cardinals - Not many clubs could lose an Albert Pujols and a Hall of Fame manager and still continue to win. The Redbirds aren't just any team.
3. San Francisco Giants - Like the Phillies, the Giants are loaded in the starting rotation, plus they should be stronger offensively.
4. Cincinnati Reds - Reds hoping St. Louis' loss is their gain. Must reverse last year's 33 one-run losses, though.
5. Arizona Diamondbacks - D-backs made quite a run in 2011 (worst to first), and should be in good shape to sustain that momentum in 2012.
6. Atlanta Braves - Need more offensive punch to place less pressure on starting pitchers. Second place seems to be the Braves' destiny.
7. Milwaukee Brewers - Doubtful Brew Crew will reach its franchise-best 96 wins of last season.
8. Miami Marlins - New ballpark and free-agent talent infusion should keep the new-name, new-look Marlins relevant all season long.
9. Colorado Rockies - Starting pitching is the pivotal element if the Rockies want to contend in highly competitive NL West.
10. Washington Nationals - Nats keep getting better, but still are a player or two and the same number of years from realizing full potential.
11. Los Angeles Dodgers - Ownership problems still linger. Hoping for a better season than in 2011. The good news is, it couldn't get much worse.
12. Chicago Cubs - There's new management and a new attitude on the North Side, but it's still the same old Cubs.
13. San Diego Padres - Not content just to rebuild, Padres' front office made several solid acquisitions in offseason to strengthen their scoring ability.
14. Pittsburgh Pirates - Making progress, but not enough to avoid a 19th straight losing season.
15. New York Mets - The one team in NL East that didn't take a step forward in the offseason. Don't expect much Mets' Magic this season.
16. Houston Astros - Another long year for the Astros, who are in 51st and final year in NL.