Look. First things first: Roberto Hernandez is not an objectively good pitcher. He's pretty bad. But there's bad and there is 2013 Phillies bad. It's all relative.
Here is what the Phillies had as starters in 2013, with only starting pitching stats included -- bullpen appearances by, say, Ethan Martin, have been stripped out. WARNING: TRIGGER ALERT: Lookit. You should say their names: Tyler Cloyd, Ethan Martin, John Lannan, Zach Miner, and, sadly, Roy Halladay.
Compare that to this: 2014's starters, to date.
Roberto Hernandez looks better than what the Phillies ran out in 2013. He costs $4.5 million this year. Lannan cost the Phillies $1.5 million last year. Halladay? $20 Million.
If you figure that Hernandez essentially is replacing Halladay, Lannan, and Martin's combined 150ish innings as a starter with a 4.14 xFIP versus an xFIP of about 5.00, the back-of-the-envelope numbers suggest that the marginal improvement should work out to be close to 15 runs over the season, or about 1.5 wins. All for $4.5 million bucks and no long-term commitment.
I had hoped that Hernandez would produce positive WAR of 1.0 and replace about 1.6 of negative WAR, but that does not appear to be in the cards -- he's been walking too many people. His strikeout rate has bumped marginally higher, perhaps from the shift to the NL where he gets to eat pitchers once in a while as opposed to facing a DH. His groundball rate and BABIP numbers are all in-line with expectations. If he can get back to a more-normal walk rate, it will help generate positive WAR, though the currently suppressed home run rate can be expected to bounce back up, too.
The bottom line here is that we saw another decent performance from Hernandez tonight that, along with lots of other key contributions, allowed the Phillies to win. Having a 5th starter who can keep a good offensive team like the Rockies (second in the NL in wRC+) to 2 runs over 5.2 innings is pretty good. It kept the Phillies in striking distance and allowed them, ultimately, to catch the Rockies tonight.
Roberto Hernandez is not going to be a world beater, but he doesn't need to be. He needs to be a win at the "5th starter" roster spot. We're grading on a curve, folks.
Given his production so far, along with the minimal cost and commitment, I'm still pleased with his signing, and I think it was a sound move during this off-season.
Here's to predictable, cost-effective mediocrity! If only the rest of this roster worked out as well.