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Breaking Down the Rotation - #1: Aaron Cook

Spring Training is under way, and we're already watching the Rockies get stepped on by all of their Cactus League counterparts. No rotation has officially been set as of yet, Starters are coming in in relief, getting pulled after 2 by hook or by crook, closers pitching the 4th, it's all crazy.

Well, that's the thing about Spring Training. It means absolutely nothing for most the players and teams. It's getting timing back. It's finding that toehold on the pitching rubber again. It's hearing your batting gloves squeak against the bat. It's going 2.1IP, 8H, 6R, 4ER, 1K, 3BB. Well, for our boys is seems to have been.

Despite the rotations' spring shortcomings, we still think we have a promising staff this season. We've touched on who I think our #2-#5 pitchers are going to be, and that brings us down to our #1, our Ace, our Opening Day pitcher, and despite the title of this article, I feel it's going to be:

Shawn Chacon

#30 / Pitcher / Colorado Rockies





Dec 23, 1977

naw I'm kidding

Aaron Cook

#28 / Pitcher / Colorado Rockies





Feb 08, 1979

Aaron Cook has been in the majors for 6 years (and a 7th year if you count his 2002 Sept. Callup), all with the Rockies, and has quietly worked his way to the top of the Rockies' Staff as possibly the franchise's most successful pitcher.

Join me after the jump and I'll tell you why.

Cook put up the best season of his career in 2008, posting career highs in K's, lows in HRs and ERA, and just missed the elusive 17-win mark that so many Rockies' pitchers dream of. Compare his 2008 numbers with his Career numbers:

ERA K/9 BB/9 HR/9 K/BB GB%
2008 3.96 4.09 2.04 0.55 2.00 55.9%
Career 4.36 3.58 2.63 0.70 1.36 57.6%

You can see the areas of improvement.

Basically, Aaron Cook has hit his stride the past few seasons, and he picked a good time to do it. He is now 30, and we know that 30 is that magic number where people start to decline (I made that up, but "The Wrong Side of 30" has its base in some sort of evidence). He's entering the 1st year of a 3 year, $30M extension that he got during the 2007-2008 offseason, which I feel is well deserved. Cook seems like the kind of pitcher I'd like to stay with Colorado for the extent of his career.

Now, we all remember the disappointment that was 2008. We remember the highs, the lows, and what was good and what was bad. During the early months of the season, when our defending NL Champs fell flat on their faces, Aaron Cook seemed to be the only pitcher who had anything good going on. He was "The Stopper," if you recall. As the season wore on, he continued to be good, and while it wasn't his best performance ever, his season "peaked" during a 3-inning relief appearance during the 2008 All Star Game in terms of national exposure and the fact that "Hey the Rockies might have some good players even if the team as a whole is falling on its face!"

The downside came during the second half of the season. A combination of the team's failure and increased reliance on Cook to stop their losing streaks eventually took its toll on Cook, and he began to see his performance slipping. Perhaps he was tired, perhaps he was mentally fatigued as well, but whatever it was, Cook was by far an inferior pitcher in the 2nd half than he was in the 1st.


I beg to differ. And FIP supports me.

1st Half 20 11 6 138 3.57 4.36 2.02 0.78 9.57 .299 4.03
2nd Hald 12 5 3 72.2 4.71 3.59 2.11 0.12 11.02 .333 3.28

Based on those FIPs, Cook was actually BETTER during the second half!

First half, Cook's success came from increased strikeout rates, even better control, and he kept that Purple Dinosaur in reasonable line. Batted balls were finding gloves, not many extraneous people were reaching base. FIP wasn't a big fan of Cook's performance, and suggested that it was going to come back down.

And so it did. Sort of. He struck out fewer in the Second half, only walked like a guy or two more, and balls were finding holes and gaps and basically landing when they shouldn't have. But here's the big thing, if you haven't noticed it yet.

Post ASG, 2008, Aaron Cook gave up 1 HR.



A single, solitary long ball. On August 4. In Coors Field. Against the Nats. To JESUS FLORES, a borderline major league catcher. (I just found that funny, he's able to shut down all the big boys he sees but watch out for AAAA backup catchers!)

FIP absolutely loves it when you keep the ball in the park, and you can see that again in the discrepancy between his 2nd half ERA and his 2nd half FIP. As a side note, I'm not for a second suggesting that FIP is the end-all pitching statistic, but in terms of the amount of work I felt like putting in, FIP is a good indicator and really easy to dump into a spreadsheet next to regular pitching data. A High FIP and a low ERA probably indicates that he also has a low BABIP and/or good defensive help, and then reverse everything and that's probably true as well. Which is funny, because Cook did both of them last season.

I know that there's more weighing in on the two halves of Cook's season, so I'm not going to champion this whole "His second half WAS better!" cause. What I want everyone to take out of it is that what a pitcher looks like and what that pitcher is actually doing tend to be two completely different things.

The reason Cook is so successful is that he's an extreme groundballer, as we all know. He's one of the best in the league. In fact, he is the third best (55.9%) behind Brandon Webb (64.2%) and Derek Lowe (60.3%). As a side note, Ubaldo Jimenez was 4th at 54.4%. Now, we've debated the effect of flyballs in Coors Field in other discussions, as in "The Greg Smith Conundrum," a fanpost by user lizardlad01, and we touched on it a bit in the Counting Rocks article on smith, but the fact of the matter is (at least right now): groundballers play more to our strengths. Tulowitzki and Barmes up the middle, and (eventually) a capable Ian Stewart at 3B and (hopefully) a healthy Todd Helton at 1B, and we have a pitcher who can get batters to hit the balls to where our best fielders are. Hence, success.

Speaking about success, now for the part where I explain why Cook might just be the most successful pitcher in franchise history.

In this case, my definition of success isn't one good season. It's many good seasons with the team. If I was going to ask whom the best pitcher in Rockies' history is, and based it all on one season, I'd more than likely go with Joe Kennedy in 2004. He was awesome, posted a 3.67 ERA (and may he continue to rest in peace). If you're asking who the most TALENTED pitcher ever to pitch here is, well, I think it could very well be Ubaldo Jimenez, or perhaps Pedro Astacio, or if you just pretend he wasn't hurt all the time, Armando Reynoso. But that's the caveat - Multiple seasons, and actual production, not what ifs, not potential, not warm fuzzies.

Aaron Cook meets those criteria. Since becoming a full time starter, Cook has posted the following ERA+ 's (from 2008-2004): 116, 116, 116, 130, 115. It's not stellar, it's not Cy Young worthy, but it is much better than average, and it's clearly consistent. Aaron Cook is a known, beneficial commodity, and the Rockies are incredibly lucky to have him.

Let's compare a few more:

Astacio (while with the Rockies, 1997-2001): 122, 83, 115, 110, 102

Jennings (2002-2006): 106, 97, 89, 95, 130

Reynoso (1993-1996): 119, 103, 101, 106 (and he was severely limited during '94 and '95)

So my claim of Cook being the most successful pitcher in Rockies' history is a bit tongue-in-cheek, as Cook isn't the most knock-down, strike-em-out, blow-em-away pitcher ever, but he's very effective, and can do it season to season. His ERA+ numbers show that he's a solidly above-average pitcher, and has been for the past 5 years. And frankly, an effective, dependable, solidly above-average pitcher for the Rockies is about as valuable to the club as any pitcher we've ever had.

So what can we expect out of Cook next season? Well, the projection is kind of dull. It's pretty much the same as this season; tweak it a bit here and there.

Bill James 29 29 11 10 182 74 51 1.45 0.69 3.66 2.52 1.43 .307 4.26
CHONE 29 29 10 10 182 82 48 1.71 0.74 4.05 2.37 1.49 .326 4.19
Marcel 11 9 182 90 50 1.80 0.69 4.45 2.47 1.36 .303 4.05
RMN 30 30 11 10 197.2 84 48 1.75 0.65 3.80 2.21 1.37 .308 4.06 4.25

So what more is there to say about Aaron Cook? He's a stabilizing cog in the middle of a rotation constantly in flux, and a leader who will help usher in this new era of Rockies pitching.