Santiago Casilla’s Success For San Francisco Giants Belies Concerning Trends

Steve Mitchell-USA TODAY Sports

In a year where most things have not gone the way of the defending World Series champion San Francisco Giants, reliever Santiago Casilla has been a notable exception.

… right?

I mean, after a “down” year in which he’d posted a 2.84/1.22 ERA/WHIP, the righty reliever’s numbers are as good as they’ve ever been this season, currently owning a career-low 1.70 ERA going into Wednesday along with a .203 BAA and 1.22 WHIP.

So why is it that he’s got a -0.2 fWAR next to his name after a -0.4 fWAR 2012? Are the numbers just inexplicably wonky?

Well … not quite.

Although the 33-year old’s counting numbers tells the Giants that what they have this season is a rock-solid reliable bullpen piece, the other story reveals a quite different side of things: one that paints the portrait of an aging veteran whose peripherals suggest serious decline — if not for the intervention of the baseball gods.

The simplest of these are going in the good ol’ strikeout and walk rates, which are both not trending in the right directions. The righty has experienced a four-year decline in the whiffs department, posting a K/9 of just 6.81 through 37 innings in 2013 to go along with a career-low (full season) 9.2 swinging strike rate. As for the walks? His 4.38 BB/9 is a four-year high.

Furthermore, Casilla’s declining velocity (six-year low 93.2 mph is leading to a spike in fly balls (28.8, 29.8, 31.4 percent over last three seasons), which is to say that he’s been relying on a wildly fluctuating home run rate (1.14 HR/9 in 2012, 0.49 in 2013) and a fortuitous strand rate (career-high 86 percent) to keep his numbers well below his 3.85 FIP.

In short, neither time or the stuff to consistently get outs are on his side — which is not what a team wants to hear when they’ve got substantial amount of money invested in him.

Even though he’s consistently well out-performed his FIP and xFIP while in San Francisco, you’d think that the Giants may want to start seriously looking to offload the $9.5 million owed to his through the next two seasons before things start to get out of hand.

After all, when a pitcher relies on things they can’t really control, it can end up being quite the slippery slope, you know?

Thom is an MLB writer for RantSports.com. Follow him on Twitter @BlueJaysRant, or add him to your network on Google

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