More trend lines! xFIP, or eXpected Fielding Independent Pitching, is intended to not only take team factors out of a pitcher's performance (FIP), but also "normalize" home run outcomes by applying a constant to Fly Balls Allowed based on averages. The stat has a pretty good history of telling you the true talent level of a pitcher once you take most of the variables out. It also, therefore, does a good job of telling you when a pitcher is legitimately pitching worse or better.
xFIP works like ERA; high is bad. The trend line follows suit; high side on the right is trending up which is bad, low side on the right is trending down is good. A flat line indicates stability and is good, as long as the number it represents is good (like, under 4 is groovy).
Cole is, until we have a better understanding of how Darvish is going to play out, the most important member of the roster. Hamels has been steady, and is legitimately pitching slightly worse this year...but not by much. He's been pretty solidly a 3.5 xFIP guy, and as you can see, Cole is sitting around 3.7/3.8 this year. The trend is good though, so there's every reason to believe he'll finish the year in fine form.
Speaking of Darvish, there obviously isn't a trend line, but his one game is one of the best starts by a Rangers pitcher this year. Optimism!
How 'bout Martin Perez? The trend is right, but that's as much because of a bad start. It wouldn't surprise me to see Martin stabilize right around 4.00; anything under that would thrill me. And take note that would put him on par with Hamels.
Solid as a rock. In fact, he was trending down to 4.00 like Perez before his last bad start. This is probably what Colby looks like all year, and once again puts him in that "#4 starter" territory.
Oh, dear. The good news is, without the one game, the trend isn't quite as bad. But it's still bad. Pitchers have managed to outpitch their xFIP for entire seasons. It's not unusual. But it's not the norm, either. If/when Holland blows up, it shouldn't be unexpected.
As with Delino Deshields, we must ask ourselves: "Was Shawn Tolleson actually performing that poorly?" As you can see, the bad appearances were getting worse and worse, and he only had a few good appearances. More importantly to Jeff Banister, I suspect, is that Tolleson wasn't predictable.
That's what you like seeing in a closer. At least the recent results. Since being made the closer, Dyson has been exceptional. Remember that big uptick at the end is the average, which I include to "normalize" the line a bit.
Matt Bush's trendline is good, but I'm not too thrilled that it's centered on 4.00. And of course, as has been a frequent topic of discussion, there are other factors to consider with Bush's quality of pitching.
Jake has been very off-and-on this year which makes his 2.5 xFIP stable trendline somewhat misleading. He's still the second-best reliever behind Dyson.
Here's Tony Barnette with two really bad appearances.
Here's Tony Barnette without the two disaster appearances. More stability would be nice, but trending from 4.00 to 3.00 is a decent indicator that he can keep filling in reliably.
This is both starting and relieving. It's about as good as it gets in a spot-starter/long-reliever.
I almost forgot about Alex Claudio, and it looks like that would have been a mistake. Not only is better at his worst than some of the other relievers, he's steadily improved. Again, remember that last big uptick is the average. I would bank on Claudio getting a lot more time, soon.
There is still a good core group of relievers here. Looking at the performance histories and trends, I'm seeing consistency as a bigger problem than actual ability. Consistency can be a function of the pitcher of course, but it can also be a function of the catcher; a position that has been highly unstable for Texas this year. It can also be a problem with game planning, and Banister is working with two new coaches this year as well.
Taking all of that in, I'm still a lot more worried about injuries and arm fatigue than I am who's on the roster. As the roster itself stabilizes, I think the relief corps will, as well.