So I guess it would perhaps be in the team's best interests to sell high on Hector to get a bat. He's pitching like an ace right now, but given his peripherals, there is almost no way he can continue this current rate of success. Or is there? Probably not.
A couple stats that not many people on Angelswin are fans of are BABIP and FIP. These stats are generally used as indicators for future success of pitchers. To spare you the boring details that even I myself am admittedly not all too familiar with, I'll simply summarize these stats: BABIP is the average of balls in play that go for hits excluding homeruns, with .300 being the average. FIP is essentially what the pitcher's ERA would be if they experienced league average results on balls in play and league average defense. There are other indicators, such as xFIP (which is exactly the same as FIP but it takes out homeruns and adds a big fat assumption on how many homeruns they SHOULD have allowed given their flyball rate. I'm not a fan of this stat personally) but I'll just use BABIP and FIP for this thread.
While it is true that pitchers will often pitch above or below their expectations given the two aforementioned statistics (Santiago has been one of them, Weaver is another), there is absolutely a correlation between these stats and what actually occurs on the field. If you look at the top 10 performers in FIP so far this year, you will not see any ERA's that stick out like a sore thumb. Conversely, if you look at the bottom 10, you will fail to find the same. Hell, look at the bottom 30. There are really just a handful of ERA's that are not anywhere near their FIP levels. Mike Pelfrey has the largest difference, with a 3.23 ERA as opposed to his 4.89 FIP. However, you'll also notice his BABIP has been favorable, at .275. That's a career low (or high), well below his career average of .310. Back on the top 30, I took a screenshot to show the biggest standouts and the correlation I am trying to make.
You'll see Kluber pitching worse than his FIP expectations, however you'll also see a .344 BABIP which is much higher than average and a bit higher than Kluber's career average. You'll find these same things with Kershaw, Gonzalez, Carrasco, and Bucholtz. Chris Sale does not have a necessarily unsustainable BABIP, however it is quite a bit above his career average. Miller, you will see, has an ERA much better than his FIP and also an absolutely ridiculous .183 BABIP. The only outlier I found in this top 30 is Burnett. I will say this is simply a small sample size to fit my argument.
"But tdawg, you can't just do that!". Fine, look at the top 30 and bottom 30 in FIP last year and the year before. All those names look familiar? Do you see many (or any) guys that are more than 1.00 points different between ERA and FIP? Do you see the correlation and point I am trying to make here?
Generally speaking, FIP and BABIP are pretty damn good indicators of what to expect from a pitcher. There will always be outliers, but they are fewer than most probably realize. Which brings us to Santiago. Before today's start, Hector had a 2.41 ERA versus a 3.98 FIP. He also has a career low .263 BABIP. Now, Hector has always outperformed his FIP and has always had a low BABIP, but never by this much. Not even close. So, given his BABIP being what it is, and his FIP being what it is, it is logical to assume he will regress. In this case, by quite a bit. That isn't to say he will end up with bad numbers, quite the contrary. It's just to say that he is currently pitching way above his head.
You're probably assuming that most, if not all GM's in baseball are aware of this. Or at least, they can become aware of it if they ask the right people. But as we saw with the Trumbo trade, as well as the Joe Saunders trade, this isn't always the case. So should the Angels sell high on Hector to get a bat? Or should they keep him and trade from their minor league wealth of arms?
In my opinion, Hector is more valuable to the team than he would be in trade. However he should absolutely be made available. If someone is willing to offer up a Justin Upton type player for Hector and a prospect or two, then you certainly have to be open to it. If the best you can do is Ben Revere, I say keep him. Despite me spending all this time trying to prove that Hector will regress quite a bit this season, I do believe he is an extremely valuable asset: He's a lefty, he's young, he's versatile, and quite frankly he's a pretty damn solid pitcher. While he won't keep up what he is currently doing, he will still provide the team with 170+ innings of sub 3.75 ERA pitching, as well as the versatility to pitch out of the pen if needed. You have to remember that while the Angels have a wealth of pitching prospects, they are still just that: Prospects. Hector has proven to be good at the major league level, and given his age and low mileage, should be good well into his 30s. In my opinion, the Angels should be looking to lock up Santiago long term, especially with Wilson and Weaver's contracts being up after next season.
So then who should the Angels trade to land a bat? The answer is obviously CJ Wilson. Wilson is pitching very well, and it appears that 2014 was more of an outlier. Despite that, we have obviously seen the best years of CJ go by and the time to trade him is now. It is likely the Angels would have to include at least some cash in any deal involving Wilson, but given his performance this year so far it would not need to be too significant. Hector Santiago is, essentially, a younger version of CJ. And if you include this year, he is a better version of CJ as well. Why trade the younger, less expensive guy when you can dangle the older one and get a contender in desperate need of pitching to give up a similar return? I believe CJ can block trades to 8 teams, but my guess is teams like Boston and New York are not on that list. San Diego is another team unlikely on the list.
To summarize, Hector Santiago is obviously pitching well above his head. But he is still a good pitcher and a valuable asset to the Angels not only short term, but long term as well. CJ Wilson is only an asset short term, and should be the main pitcher the Angels look to trade this year.