Felix Hernandez has pitched a boatload of innings

Things you probably know about Felix Hernandez:

• He plays for the Seattle Mariners.

• He is very good at throwing baseballs.

• He has an exceedingly winning smile.
  

Things you may not know about Felix Hernandez:

• He has won every Elvis impersonation contest that he has entered.

• In the off-season, he's contracted by NASA to throw fastballs at the moon to help them better understand the physics of meteorite impacts.

• He's the first player in 21 years to throw more than 2000 innings before turning 29 years old.

Oh, hey. That last fact segues perfectly into today's post. How convenient...

Over the last 70 years (since WWII), 3540 men have been employed as starting pitchers in Major League Baseball. Of those, only 198 have pitched at least 2000 innings. Of those, only 14 have surpassed the 2000 innings mark before their 29th birthday. Dwight Gooden was the most recent player to accomplish this feat (back in 1993), until Felix pitched his 2000th inning last year in July against Baltimore.

2000 innings is a lot of innings. For perspective, in his entire MLB career, Hideo Nomo pitched fewer than 2000 innings. Same with Jason Schmidt. And Carlos Zambrano. And Jarrod Washburn. These are guys who seemed like they were around for a loooong time, and Felix has already surpassed them in innings pitched. Sometimes it's difficult for me to comprehend that next year will be Felix's ELEVENTH season as a member of the Seattle Mariners. That fact is bananas.

Anyway, like I said, 2000 innings is a lot. Despite being not-old, Felix's arm already has a lot of mileage on it. Although he hasn't shown signs of slowin' down (his fastball in 2014 was actually ~1 mph faster than it was in 2013), should we be at all concerned about the number of innings he's already thrown? Is this something that could potentially contribute to an early end to his dominance or career? (I did just mention Dwight Gooden in the previous paragraph. I don't want the second half of Felix's career to in any way resemble the second half of Gooden's career...) To try and get some sense of what Felix's future might hold, I used FanGraph's WAR graphs tool to plot the career trajectories of all of the men (since 1945) who accumulated more than 2000 IP before they turned 29.

This is a list that includes (at least) five Hall of Famers! That's some pretty decent company for Felix to be in.

Before their 29th birthdays, these men pitched a combined 141 seasons, averaging more than 4 WAR and 220 IP per year. Alternatively, after turning 29, they pitched 88 seasons and averaged just 2.1 WAR and ~170 IP per season. Additionally, more than half of these pitchers failed to pitch beyond the age of 33. These numbers represent a decline that is disconcertingly steep. Although Blyleven, Sutton, and Robin Roberts each continued to pitch well throughout their 30s, a ~three in 13 chance of not tanking doesn't strike me as particularly appealing. I want Felix to dominate until he's 40! Of course, pitcher's do generally start to decline in their late 20s, so maybe these trends aren't too far from normal?

For comparison, I went and looked at all of the players who, since 1945, threw 1000 innings both before and after turning 29. There were 90 such men. (This seemed like a not-bad baseline for how the "average" successful MLB pitcher might decline with age.) The WAR/200IP for the earlier parts of these men's careers was 3.37. After they turned 29, their WAR/200 dipped a little bit to 3.09. This represents a drop of less than 9%. Conversely, the 13 men who threw 2000 innings before turning 29 had a WAR/200 of 3.67 before their 29th birthdays and a WAR/200 of just 2.41 after turning 29 years old. This drop off (more than 33%!) is much more significant, suggesting that throwing so many innings at a younger age might indeed adversely affect the length of a pitcher's career.

If Felix's career follows the average trajectory of the 13 players listed above, then he has already accumulated more than 75% of his total value as a starting pitcher. That would put him on pace for a career WAR of about 62.5, which would rank 46th all-time among starting pitchers: a bit below Tom Glavine and a bit above Early Wynn. That would certainly represent a wonderful career, but I have the feeling that most Mariners fans are (realistically or not) hoping for a bit more from The King. Alternatively, Felix could pitch well into his 40s, racking up 100+ WAR! Or he could struggle mightily next season, and fail to ever find his groove again. Although the odds seem to suggest that Felix's best years might be behind him, #34 has proven himself to be exceptional time and time again. We'll just have to wait and see.

Regardless, it does appear as though Felix's high innings total is a reason to be at least a little bit concerned. (If you weren't already somewhat apprehensive about this, I apologize for burdening you with something else to worry about.) However, there are still lots of reasons not to freak out:

• Felix has already proven to be adaptable in his pitching style, changing from ~a fastball pitcher earlier in his career into someone who has come to embrace his offspeed stuff more and more. This ability to adjust his game plan will certainly go a long way in helping to prolong his career.

• Felix has never suffered any serious injuries in the past. As silly as it sounds to say, it's important to remember that having avoided injury in the past is probably the best way to avoid injury in the future.

• Sports science has advanced dramatically over the past 20 years. Doctors/trainers certainly don't know how to prevent injuries 100% of the time, but the techniques/treatments that Felix has available to him now are certainly better than what was available to the likes of Fernando Valenzuela or Dwight Gooden. This should give Felix a better chance to overcome any setbacks that he might encounter.
  

In closing, this post should serve as another reminder to appreciate Felix now. Strive to avoid taking him for granted. Hopefully Felix's dominance will continue for another decade, but you should do your best to cheer for him as if each start is his last; you never know when the King's reign will come to an end.

Go M's.