What is the Most Successful MLB Expansion Team

So, what makes a successful team? The Yankees, as the gold standard of major league baseball has a lifetime winning percentage of .567 - 9383 wins, 7162 losses. Here's a look at the Major League Expansion teams.

Using the metric of winning percentage, the most successful expansion franchise is the 1998 addition, Arizona Diamondbacks with a .505 winning percentage. As far as major league teams, without the additional moniker of "expansion team" go, the D-Backs are twelfth in terms of winning percentage.

We all know the New York Yankees are the undisputed dynasty in Major League Baseball - 26 World Championships. In terms of winning World Series championships, three of the expansion teams have won two world titles: The New York Mets, Toronto Blue Jays, and Florida Marlins. However, while the Mets were one of the "original" expansion teams, and the Blue Jays have been in existence since 1977, the Marlins came into being in 1993 and won their first world in 1997 after six seasons.

Three other teams have won one title each: the Diamondbacks, Royals and Angels. The Angels took over 40 years to win a title, the Royals won it all in 18 years, and the Diamond Backs won in four. The Blue Jays won their titles back to back; the Marlins won theirs against the then-current champion Yankees and the Indians, a team unable to win a title since 1948; the Mets who went from one of the worst teams in major league history to world champions in 7 years. The Mets have also won the National League pennant four times, the most of any expansion team. Sadly, though, no one remembers who came in second place. This would be a meaningful tiebreaker, and while a league title is a fine achievement, it pales to winning it all.

So then, which is the most successful expansion era team? The Arizona Diamondbacks with a .505 winning percentage; the number of world series championships is split between the Mets, Marlins, and Blue Jays. The time to win the first championship is split between the Diamondbacks and Marlins. The Marlins have one of the worst winning percentages of this group, with a .470 mark (1112-1251) while the Diamondbacks have the best.

So while baseball is ultimately about winning it all, it is also about consistency. And while in terms of the overall context of baseball as a whole, the Diamondbacks winning percentage of .505 is good, but in the middle of the pack, it is well above the next best expansion-team performer, Houston Astros (3652-3672, .498) and the only one of the group above .500. Combined with their 2001 World Series Championship earned in four years of existence, it is my contention the Arizona Diamondbacks are currently the most successful expansion team.

STATISTICAL REFERENCE:

http://www.baseball-reference.com/teams/