The top priority for the Marlins is boosting the pitching staff that suffered a devastating blow upon the death of Jose Fernandez. That can’t be forgotten, but at the same time, it’s as good as unfair to other pitchers to lead with this, because Fernandez could have no suitable replacement. The Marlins were robbed of one of the greatest talents on the planet. The Marlins just signed Edinson Volquez. Volquez has his things he can do, but he’s a far cry from being a franchise cornerstone. The more the Marlins attempt to move on, the more we’re all reminded of what they’re trying to move on from.

The Marlins did need some kind of starter. Edinson Volquez is some kind of starter. They gave him two years and $22 million, even though last year Volquez had an ERA in the mid-5s. A couple years ago the Royals gave Volquez an almost identical contract following an ERA of 3.04. Behold the death of ERA! Anyhow, the analysis here is simple. The last three years, Volquez has averaged about 1.6 WAR. Plugging that into our contract tool and accounting for Volquez’s age yields an estimated two-year contract worth…$22 million. Super. What gets me here isn’t Volquez joining the Marlins. It’s the story of Volquez, and the story of many a live-armed starting pitcher.

Volquez’s big-league career began with fits and starts, but he established himself with a breakthrough 2008. That was his age-24 season, and he was so good he earned a few Rookie of the Year votes even though he was ineligible for the award. Volquez has been a regular big-leaguer since, and early last July he turned 33. Volquez ages at the same speed as everyone else.

In another way, though, he doesn’t. Think about pitchers and the aging curve. What tends to happen? Pitchers are expected to lose velocity. Here is how Volquez’s average fastball has aged since his first full year:

There’s one little blip there, but it’s insignificant. Otherwise, this shows enviable consistency. Volquez today has basically the same stuff he had when he was an All-Star. To keep this up over nine years is fairly unusual. Just as before, Volquez throws a fastball between 93 – 94. That’s accompanied by a sharp curveball, and he also has a changeup that he loves. The changeup has remained about 10 – 11 ticks slower than the heater. By pitch values, Volquez’s changeup stands as his best weapon.

So Volquez’s repertoire hasn’t changed much. More recently he’s gone to more two-seamers instead of four-seamers, but that hasn’t meaningfully altered his profile. Fewer walks, fewer strikeouts. Sharp, intriguing stuff, with come-and-go control. Volquez has never been renowned for his ability to locate. The way I like to think of this is as a probability distribution. Since 2008, Volquez has had nine reps. Nine attempts to have the same season. On average, he’s been worth about a win and a half. That’s what the Marlins are paying him for, but here’s how those individual seasons have actually gone:

Just based on this, we could say there’s a 1-in-9 chance Volquez looks like a No. 1 or No. 2 starter. There’s a 1-in-9 chance Volquez looks like a No. 3, and then there’s a 2-in-9 chance Volquez looks like a No. 4. Four times out of nine, Volquez has been worth at least what the Marlins expect. Five times out of nine, Volquez has underachieved, either because he’s gotten hit a little more, or because of injury. Volquez himself has barely changed at all, but this is the spread of results that he’s generated. This is what so many pitchers are. Consistency in results is a nice idea but it’s distinctly uncommon.

It’s not all that different if you go with runs-based WAR instead. Three times out of nine, Volquez has been worth at least 3 wins. Three times out of nine, he’s been at least a little worse than replacement. And another three times out of nine, his WAR has fallen between 0.5 and 1.5. Once again: same pitcher. For all intents and purposes, anyway. Volquez has barely changed, but the results have changed around him, and we’re so often reminded that pitchers have less control over what happens than we want to think.

The story of Edinson Volquez is the story of so many live arms who have their issues throwing strikes. If you give one of them an opportunity, that pitcher could rip off just enough good starts that his overall numbers look great. Short of that, there could be start-to-start inconsistency, even if the innings totals pile up. And then as the worst-case scenario, the pitcher can be bad, hurt, or both. All of these outcomes are realistic even if you hold the true-talent level steady. Edinson Volquez still has about the same true-talent level as he did when he was a non-rookie Rookie of the Year candidate. Time has increased the sample size and revealed what Volquez really is. Individual seasons are insufficient samples, but that’s what leads to the upside and downside. A pitcher like this can look good or bad a little more often than usual. And then that controls the narrative of the year, even if the pitcher’s raw ability has stayed constant.

I’m not sure how well I’ve expressed this thought. And it’s not a new idea to think of players as generating a range of potential outcomes. Volquez has generated a broad range, even as he’s remained very much Edinson Volquez. I guess this is just another reminder of how much baseball can vary, in ways you can’t foresee. Different outcomes don’t always reflect different inputs. Volquez has had almost a decade of similar inputs. The Marlins still can’t know what they’ll actually get. Not, at least, in the box scores. Every strike-challenged live arm is a roll of the dice.