clock menu more-arrow no yes mobile

Filed under:

Is Trevor Cahill a Big Loss?

An interesting comment was made today that got me thinking, it was by my Tarp Talk (shameless plug: we started an A's podcast!) colleague an AN frequenter cuppingmaster who tweeted,

"Call me crazy, but I don't like evaluating this trade for Cahill (or any really) on the basis of future WAR/surplus value."

I don't know if I entirely agree on this. In some ways I do, WAR can be a bad method of analyzing trades which is something brought up by the one-year rentals of David DeJesus and Josh Willingham. The goal was to compete now and looking at the value of the pieces sent to Kansas City and Washington for so long as they remain in those organizations seems sort of foolish. Had Oakland competed and made the playoffs care of contributions by DeJesus and Willingham and yet still left the organization one may have said that value was in and of itself important. Furthermore one must discount the future value of players, if Justin Marks becomes a lockdown closer for the Royals in 2013 or 2014 that is great, but his value was best to the A's for getting a piece that helped them reach the playoffs. Of course, it didn't work out that way and we can debate a million ways past Sunday how to best look at that deal now but I think cuppingmaster makes a very salient point. However when it comes to surplus value, I think there is more there - we just don't know how to monetize other goals. For example a trade like Pittsburgh's last year to get Derrek Lee from Baltimore and Ryan Ludwick from San Diego may not have made much of a big deal WAR or traditional surplus value-wise, however that served as a signal that Pittsburgh planned to be aggressive and that has value to people who free-agents considered the Pirates and who may question their commitment to winning. There are other ways of valuing trades, but we just can't figure out how to necessarily quantify them.


Ultimately a hybrid of WAR, surplus value and here I will say it: feel, has to go into any analysis of a trade. But instead of projecting the future, let's realistically look first at the asset we traded whom from aside from a short period of time early in 2011 when Cahill duped me, I have not thought he is a very impressive pitcher. Lots of his supporters will say he is 23 can grow better himself etc and they argue we are looking at the starting point on a career long bell-shaped curve as opposed to the flatter line, I propose. But just how good or not good is Trevor Cahill? Bill James in his prognostication for 2012 says Cahill will regress to 5.8 K/9, better his control slightly to 3.4 BB/9 while he allows slightly more home runs (1.0 HR/9). James thinks he will do worse than he has the past two seasons with his FIP ballooning to 4.40. The truth is Cahill hasn't yet even been all that impressive, a look back:


K/9 BB/9 HR/9 K/BB FIP
2009 (4.5) (3.6) (1.4) (1.25) (5.33)
2010 (5.4) 2.9 0.9 (1.87) (4.19)
2011 (6.4) (3.6) 0.8 (1.79) (4.10)

The numbers in that chart are pretty straightforward - but why all the brackets? For a lack of a better method (coloring the text just didn't work for whatever reason) the bracketed numbers represent the instances where Cahill's numbers fell below league average. As you can see that happened frequently: he is not a strikeout pitcher, his control is evidently worse than average even if his control is good his lack of strikeouts gives him a paltry K/BB ratio and subsequently his FIP is routinely worse than league average as well. The one category he excels at - and believers of defense-independent metrics will agree it is a significant one - are limiting home runs. But of course Cahill has received some help in that respect having pitched at O.Co Coliseum for around half his starts. While not as significant a split as I'd expect here is how Cahill has fared on home runs at and away from the Coliseum the past three seasons:


IP HR HR/9
O.Co Coliseum 319 1/3 33 0.93
Elsewhere 263 2/3 32 1.09

As a surprise to no one the number goes up. Of course Chase Field is not O.Co Coliseum as we can see here:

PF HR Oakland PF HR Arizona Difference
2009 0.927 1.042 .115
2010 0.701 1.063 .362
2011 0.786 1.095 .309

Cahill betters the HR/9 average by merely a tenth of a home run every nine innings, it seems like particularly in the two years that he bettered the league average HR/9 when the disparity between Oakland and Phoenix was significant that'd push him over that threshold making him below league average there. This is why I have been describing Cahill as at best a fourth starter all this time, because that is in fact what he is - few teams would expect a fourth starter to exceed league average in all these categories otherwise they have a phenomenal staff or should rearrange their starters.

Let's get back to the 23 year old argument - that Cahill at 23 has yet to really shine yet and is still maturing. Bill James' similarity scores through age 23 brings up some interesting pitchers of recent vintage. To keep a relatively similar era I've only included pitchers more recent than 1980 they are: Alex Fernandez (most similar), Mark Gubicza (second most similar), Jim Abbott (sixth most similar), Greg Maddux (seventh most similar) and Tom Gordon (tenth most similar).

K/9 BB/9 K/BB K/9 BB/9 K/BB
Player Through age 23 Age 24 and beyond
Cahill 5.5 3.3 1.64 ??? ??? ???
Fernandez 5.9 3.0 1.97 6.7 2.7 2.50
Gubicza 5.4 3.9 1.39 5.6 3.0 1.90
Abbott 5.3 3.1 1.73 4.4 3.5 1.27
Maddux 5.3 3.3 1.60 6.2 1.6 3.96
Gordon 8.7 4.7 1.84 8.1 4.0 2.03

In more non-surprising news we now learn that for the most part pitchers up to age 23 do not make giant leaps and strides and change the type of pitchers they are going forward - one exception on this list is Greg Maddux - who as a pitcher in general is an exception as he is likely future Hall of Famer. Maddux however just did it on the control side, he learned he was going to strike out many guys and instead made sure he didn't give teams extra outs via the walk. His strikeout rate merely upped itself 0.9 K/9 after age 24 while the walk rate was more than halved. Only Jim Abbott got worse beyond age 24 of this group so I anticipate that Cahill will improve but turn into a completely different pitcher? It seems unlikely, so therefore what we can expect out of Cahill is more of the same. Perhaps his 4.10-4.20 FIP drops to 3.90-4.00, which is good but still doesn't elevate him to the level of an ace on a contending club.

We have no idea what we have in the three players we received from Arizona, but the ceiling for Jarrod Parker in particular seems to be much higher than that of a number four pitcher. It is a gamble, make no mistake of that, but if you are rebuilding, trading Cahill for Parker and more could potentially pay off because frankly Cahill wasn't much to write home about to begin with.