The other day, August wrote about how the Tigers’ bullpen was in desperate need of improvement. That is, if the Tigers intend to compete in 2016, and they do intend to compete in 2016, while simultaneously trying to keep the longer-term picture in mind. So it made sense when, earlier Wednesday, reports came out the Tigers didn’t love the asking prices for the higher-tier relievers available. It’s not like the Tigers have all that much youth to move around, anyway. This all led to an unsurprising end: the Tigers have picked up the more affordable Francisco Rodriguez, from the Brewers. The Brewers are getting a low-level prospect. There are some players to be named later. This will probably just be remembered as the Rodriguez trade, if it’s remembered at all.

Of course a team in the Brewers’ position had little reason to hang on to a veteran closer. And of course a team in the Tigers’ position was looking to add a veteran closer. Doesn’t get more veteran closer-y than picking up the active leader in career saves. You could say Rodriguez is only 34 in January, and that’s true. He’s also looking ahead to his 15th season in the major leagues. He’s survived for a long time, and he’s even thrived for a long time. You can only do that by adapting. Francisco Rodriguez is a tremendous example of how a pitcher should want to age.

I mean, ideally, you age without showing any external signs of it. Ideally you show up throwing 96 and you go out throwing 96. Ideally you can be a rare physical freak, but you don’t want to bet on being a freak, even if you are special and the only you in the whole wide world. Age affects everybody, even elite-level baseball players, and the key is to change without getting worse. Rodriguez might not be the pitcher he once was, in terms of his overall dominance, but he remains a good closer, despite age having drained his raw skill.

A decade ago, Rodriguez’s average fastball flew at nearly 95 miles per hour. Of all the pitchers who threw at least 50 innings, that fastball velocity put Rodriguez in the 95th percentile. He was, legitimately, a flame-thrower.

Last year, Rodriguez’s average fastball flew at just shy of 90 miles per hour. Of all the pitchers who threw at least 50 innings, that fastball velocity put Rodriguez in the 16th percentile. He was, legitimately, a soft-tosser.

A decade ago, Rodriguez posted a K-BB% of 24%. Last year, Rodriguez posted a K-BB% of 24%.

There are some differences in the profile, of course, and Rodriguez was a little better a decade ago, but he managed to approach that old level of success throwing about as hard as Mike Fiers and John Danks. This is what aging tends to do — it saps a pitcher’s top velocity. Rodriguez has lost a lot of his, but what he’s clearly learned to do is compensate. As such, Rodriguez just managed a career-high rate of strikes thrown. And he also allowed a career-low .229 OBP, putting him points ahead of Zack Greinke, Jake Arrieta, and Clayton Kershaw. It doesn’t matter that .229 presumably doesn’t measure Rodriguez’s actual true talent. His sustaining effectiveness is the point.

It’s easy to explain. It’s awful hard to pull off, but it’s easy to explain. The young, dominant version of Rodriguez had a big fastball and a sharp breaking ball. As he got older, he picked up a change, and now that changeup is a primary offspeed pitch, bordering on a primary overall pitch. Career fastball and changeup trends:

A change showed up as early as 2003, but it didn’t really count as a real thing until 2007, and it’s taken off from there. Last season, Rodriguez threw almost as many changeups as fastballs. If these trends continue, then 2016 will have Rodriguez using a fastball as a change of pace from the changeup, so to speak, instead of the other way around. Rodriguez was already changeup-heavy in 2014, when he allowed 14 home runs. Then he increased his changeup usage by almost half, subtracting mostly from the heater. Far fewer baseballs flew over the fence.

As the fastball has gotten worse, Rodriguez has moved away from it. As the breaking ball has gotten worse, Rodriguez has moved away from it. And as the changeup has gotten better, Rodriguez has favored it, and based on recent indications, it could stand to be thrown more often. Last year, by pitch values, Rodriguez’s fastball was at a career low. Meanwhile, his changeup was at a career high, at +18 runs above average. There’s noise in there, I know, but that’s an impressive figure for a one-inning reliever. Based on our leaderboards, only Greinke and Danny Salazar finished with a higher 2015 changeup run value. Rodriguez was ahead of Cole Hamels and Marco Estrada.

Rodriguez has learned to control the pitch, and with control comes command, and with command comes trust. So now we have Francisco Rodriguez more or less pitching backwards. Here’s a plot covering the PITCHf/x era, of Rodriguez’s fastball usage in counts with more balls than strikes.

Last season, he approached 50%, meaning even in traditional fastball counts, hitters often didn’t get fastballs. Lefties got changeups, early and late, ahead and behind. Righties got changeups, early and late, ahead and behind. Rodriguez doesn’t have the stuff to blow hitters away anymore — as a starter, he’d qualify as a rare crafty righty. He’s learned another way, outsmarting the opposition like so few young power pitchers go on to do.

The name that came to mind immediately for me was Trevor Hoffman. This is how Hoffman survived for the bulk of his career, and it’s only a partial coincidence Hoffman is a bit higher than Rodriguez on the career saves list. But another, more recent comp could be Koji Uehara, even though he throws more of a splitter. Uehara throws his splitter enough to try to keep hitters off his mediocre fastball. When something goes wrong, there’s a dinger, but in between all the dingers, there’s an awful lot of outs. This is where Rodriguez is, as he’s learned to throw more and more strikes.

I’m not going to lie to you — when Rodriguez was younger, I didn’t figure him for the kind of guy who’d grow older and easily evolve. I figured he’d be too stubborn, too resistant to the finesse-pitching lifestyle. But you know what feels great? Strikeouts and saves. Rodriguez still gets them, as he’s learned to take something off. You can worry about a fastball, or you can focus on the fastball-changeup differential. Rodriguez has gone for the latter, and so, while he has to stop getting hitters out at some point, he’s already extended his career a few seasons. What would be a few more? It’s almost 2016, and Francisco Rodriguez still works.