Could Phillies' rotation make history?

Last season, the quartet of Roy Halladay, Cliff Lee, Roy Oswalt, and Cole Hamels each compiled at least four wins above replacement (WAR), according to baseball-reference.com. Halladay led the pack at 6.9, followed by Oswalt at 5.1, Hamels at 4.7, and Lee at 4.3. Truly great seasons individually. Now, they’re all teammates with the Phillies.

Lee, of course, spent his 2010 season with the Seattle Mariners and the Texas Rangers. Oswalt spent the first half with the Houston Astros. These four aces together is an ominous cloud looming over the rest of the National League. How common is it for four teammates to each produce 4 WAR? I went to Baseball Reference's Play Index to find out.

My constraints were as follows: the pitcher must have pitched between 1960 and 2010, compiled at least 4 WAR, started in 80 percent of his games and qualified for the ERA title. There were 1,017 seasons that qualified. The only fearsome foursomes to accomplish the feat as teammates were:

1991 Atlanta Braves: Tom Glavine (7.4), John Smoltz (4.7), Steve Avery (4.5) and Charlie Liebrandt (4.3).

1997 Atlanta Braves: Greg Maddux (7.3), Tom Glavine (5.0), John Smoltz (4.5) and Denny Neagle (4.1).

There were 16 teams in Major League Baseball until 1962; 20 through '68; 24 through '92; 28 through '97; and there are 30 presently. That gives us a total of 1,278 opportunities for pitching staffs to accomplish this four-by-four feat. Only two made it -- .16 percent.

The Phillies' starting rotation could truly post some historically great numbers in 2011, but it will be difficult. Health is a big factor. As many pessimists have pointed out, the Phillies' starters are no spring chickens and have some familiarity with major league medical personnel as well. It is rare that a team gets through a 162-game season unscathed.

Knowing this, maybe it was a good idea that general manager Ruben Amaro did not rush to trade Joe Blanton (who, by the way, posted 4.1 WAR in 2007). Still, if any rotation is going to jump into the top-three best since 1960, the 2011 Phillies would be the clear favorites. It will be an intriguing year for Phillies fans, and a potentially depressing one for fans of the Braves, Marlins, Mets and Nationals.

Bill Baer is the author of the Phillies blog Crashburn Alley. Follow him on Twitter @CrashburnAlley.