The Extremity of Wilton Lopez

There’s a fun game I’ve enjoyed playing, called Spot The Half-Decent Astro. It’s challenging, because there haven’t been very many of them, and because I could never get anyone else to play too. Did you know that the 2012 Astros’ team leader in home runs was Justin Maxwell? Do you know anything about Justin Maxwell, aside from his name and that fact? The Astros have been dreadful for a reason — they haven’t had very many good players. One of their few good players has been reliever Wilton Lopez. Now Wilton Lopez isn’t an Astro anymore.

Basically. The Astros and Phillies have unofficially swung a trade, sending Lopez to Philadelphia, and sending a prospect or two or more to Houston. Without knowing anything about the prospect(s), it’s a sensible trade for Houston, because what they don’t need right now are good relievers. And it’s a sensible trade for Philadelphia, because it makes them better now and the Phillies are all about the now.

The Phillies have been in the market for a setup man. What they’ve observed is reliever Brandon League getting three guaranteed, expensive years, and reliever Jonathan Broxton getting three guaranteed, expensive years. They reportedly spoke with Ryan Madson, but those talks didn’t get far, probably because Madson wanted to close and he found a closing opportunity in Anaheim. In Lopez, the Phillies found an alternative to paying free-agent prices for help in the bullpen. They’re still paying a price — prospects, after all, can be distilled to mathematical valuations — but that price isn’t reflected in payroll.

Setting up for Jonathan Papelbon will be an adjustment for Lopez, because last year he wound up as the Astros’ closer, and it would appear he got used to the job:

That’s a save celebration. Wilton Lopez developed a save celebration. He’s going to have to abandon it now, or turn it into a hold celebration. Note: a 2012 Astros closer recorded saves.

Anyway, I’m just going to guess you don’t know a whole lot about Wilton Lopez. There are lots of relievers who are varying degrees of unfamiliar, and it’s not like the Astros have been worth paying particular attention to lately. As it turns out, Lopez is unusually interesting. Not because he’s 29 years old and right-handed. Plenty of people are both of those things. Not because he’s from Nicaragua or because he’s under team control for another three seasons. Lopez has been quite good, and in an abnormal way for a relief pitcher.

Lopez became a regular in the Astros’ bullpen in 2010. Over three years, he posted a 2.64 ERA, with peripherals to match. His specialty hasn’t been hit prevention, which is good, because hit prevention is generally unreliable. It’s been grounders and strikes. Take a look at Lopez’s 2012 video highlights on MLB.com. There are 17 of them, all featuring recorded outs. Just two of them feature strikeouts. It’s not that Lopez doesn’t ever generate strikeouts — he generates plenty of strikeouts! — but that isn’t his strength. At a time when baseball seems to be trending toward fewer and fewer balls in play, Lopez has gone a route that isn’t exactly the Ernesto Frieri route.

Since 2010, 163 different relievers have thrown at least 100 innings. They’ve averaged 7.8-percent unintentional walks, and a 44.7-percent groundball rate. Lopez has issued 3.1-percent unintentional walks, with a 55.6-percent groundball rate. By walk rate, he’s been two standard deviations better than the mean. By grounders, he’s been more than one standard deviation from the mean. I was curious about this pitcher type, so I set up a leaderboard, sorted by the sum of those standard scores. The top ten:

• 3.30, Wilton Lopez
• 3.06, Jim Johnson
• 2.77, Kameron Loe
• 2.71, Brad Ziegler
• 2.61, Scott Downs
• 2.60, Mariano Rivera
• 2.50, Matt Belisle
• 2.47, Edward Mujica
• 2.42, Ryan Webb
• 2.39, LaTroy Hawkins

That’s Wilton Lopez at the very top. In terms of combined walk and groundball rates, he’s been the most extreme reliever in baseball, just ahead of Jim Johnson, who’s blossomed with the Orioles. Lopez has thrown better than two-thirds of his pitches for strikes over this span, and he’s thrown an awful lot of two-seam fastballs. He throws four pitches in all, and three of them go for a ton of strikes, and three of them generate grounders. Like Johnson, Lopez hasn’t been a strikeout machine. Like Johnson, Lopez hasn’t had to be.

If you’re wondering about the other end, it won’t surprise you to learn that Carlos Marmol is the most extreme reliever in the other direction. His walk rate has been more than three standard deviations worse than the mean, and his groundball rate has been nearly one standard deviation below the mean. Interestingly, Lopez joins Antonio Bastardo and Josh Lindblom as setup men in the Phillies bullpen. On the sum-standard-score leaderboard, with Lopez ranking first out of 163 relievers, Bastardo ranks #161, while Lindblom ranks #147. Bastardo is all about strikeouts and fly balls, with a number of walks. Lindblom has been similarly, but less, extreme. Lopez is a completely different look, and thus a completely different option.

If it’s a strikeout that the Phillies need in the eighth inning, there’s Bastardo. If it’s a double play that the Phillies need in the eighth inning, there’s Lopez. If it’s general success that the Phillies need in the eighth inning, they now have a wider variety of options. Lopez has his vulnerabilities, but he doesn’t have very many of them, and as far as you can trust a reliever to be good in the future, you can trust Wilton Lopez. Which is to say, you can trust Wilton Lopez some.