Pitching Under the Radar: Dan Haren's Amazing Season

Thomas HillContributor IJuly 21, 2009

Has anyone really noticed what Dan Haren has been doing to hitters this season?

Many people know he made the All-Star Game for the third straight time this year, but few realize how lights out he has been every five days when he takes the ball. Even in Arizona, where Haren is the Diamondbacks’ ace, it’s doubtful people understand just how phenomenal he has been.

Currently atop the National League leader-board in ERA (1.96), complete games (three), and innings pitched (138), Haren's WHIP and ERA truly show his dominance in '09.

With the way fantasy baseball has spread like wildfire over the past decade, many people have been introduced to walks plus hits per inning pitched (WHIP). Anything under 1.1 is considered to be pretty good, and anything under one is considered absolutely amazing.

WHIP is a great statistic because not only does it take into account a pitcher’s ability to not allow hits—usually a byproduct of great “stuff”—but also a pitcher’s ability to consistently throw strikes—a byproduct of great control. Not surprisingly, pitchers with WHIPs under one are usually the game’s elite hurlers.

While there have been 202 individual seasons in which pitchers finished with WHIPs lower than one, the number shrinks markedly when you look at single season WHIPs under .9— 38 individual seasons all-time.

Now let’s get back to Haren.

His WHIP this year is an astounding .8043, which, if the season were to end today, would rank fourth all-time for single season WHIP. The only pitchers in the history of the game to have WHIPs lower than .8043 are Walter Johnson in 1913, Guy Hecker in 1882, and Pedro Martinez in his unhittable 2000. Hopefully that puts Haren’s '09 into perspective in terms of how tough he’s been on the opposition.

But we still have ERA+ to look at.

ERA+, or Adjusted ERA, is used to more accurately compare pitchers across different eras because it adjusts a pitcher’s ERA according to their ballpark. 100 is the benchmark for exactly league-average. Haren has consistently finished with an ERA+ of 108 or better in each of the last four seasons, topping out at 137 and 138 in the last two seasons.

This year, he’s making a bid to reach the top of the league in ERA+ for the first time with an incredible Adjusted ERA of 230.

Finishing the season with an ERA+ of 230 would place Haren in the top 11 all-time, matching the mark set by Christy Mathewson over 100 years ago in 1905. The all-time single season record is held by Tim Keefe, who set the mark in 1880 with an ERA+ of 294. The only pitcher to challenge Keefe in baseball history was Martinez in 2000, when he ended up at 291.

While it remains to be seen whether Haren can maintain his season of pitching supremacy for the rest of the season, these statistics should shed some light on his performance thus far in 2009.