Is this the end of starting pitchers as we know them?

As much as we want to believe that baseball is timeless and unchanging, the truth is that it's constantly evolving. New strategies get tested and adopted. If they prove successful, they spread like wildfire, with clubs copying one another so as not to be left behind in the arms race. If MLB's Mike Petriello (an incredibly smart guy worth listening to) is right, however, we're on the verge of one of the most striking evolutions in the history of the sport.

Yesterday, Petriello wrote about getting rid of "starter" and "reliever" labels, and severely limiting the number of batters faced by pitchers who start games. Here's Petriello in his own words:

"Rather than looking at the first pitcher as "the starter, who has to get me through seven innings," teams ought to simply think about 27 outs and how best to get them. If that means the best scenario is that the first pitcher gets just 10 outs, the next comes in for three, and then a third gets eight outs to get through the first seven innings, then so be it. If that reminds you of the way things work in the postseason, it should -- if it's good enough for the most important games of the year, then clearly there's something to it."

The underpinning for Petriello's objections with the way that starters are used today is that pitchers have a dramatically higher OPS against the third time through the batting order than on either the first or second time (.771 vs .705 and .731, respectively). Comparatively, relievers have a .699 OPS on their first run through an opposing team's lineup.

On its surface, Petriello's argument makes sense. If your club's goal is to prevent runs, one of the best things you can do is to simply go to the bullpen earlier. His prime example, the Rays, did that and rode a relatively unexceptional group of arms to the 9^th best run prevention in baseball. Petriello's ideal scenario is, when you don't have a true top end starter or two to rely on, to use "short starters" for two trips through the order, and then remove them for a parade of relievers.

We also certainly saw how effectively the Royals have shortened games with their incredibly deep and talented bullpen in the postseason. And we saw how sticking with Matt Harvey came back to bite Terry Collins and the Mets. Both analytically and anecdotally, the theory seems sound.

It's where the rubber hits the road that I think Petriello's plan falls apart. For one thing, it relies on having a bevy of available relievers. While the Rays were able to stave off overuse by shuttling the back end of their bullpen back and forth to Durham, the simple truth is that that is a short term solution. It may be sustainable while you have enough pitchers with option years remaining, but once those option years start getting used up, it becomes far more tricky.

Moreover, the strategy relies on actually having quality relievers available at AAA to tag in. It doesn't do the Rays much good, for instance, if they have to bring up Kirby Yates for another 20 appearances if he's going to allow another 10 home runs. The more relievers you have to shuffle into this bullpen deck, the more reliant your team becomes on inferior relievers. Indeed, the supply of effective relievers, while large, is not infinite. If these new usage patterns are indeed "the wave of the future," as Petriello suggests, teams will have to uncover a lot more pitchers to make it work.

And it's in employing these new pitchers that I think Petriello's ideal pattern becomes unworkable. Each time Major League Baseball has expanded it has created jobs for more pitchers and hitters. Each time Major League Baseball has expanded, the level of offense around the game has risen simply because it's harder to find good pitching than good hitting. So if more teams do, in fact, start employing this strategy, offense is going to counterintuitively bounce back and that difference between a starter going through the order a third time and a reliever working his way through one turn of the batting order is going to shrink, perhaps significantly.

How much? I don't know. I'm not a math guy. It seems likely that there is room for a couple of teams to do what Petriello describes the Rays doing last year. But the more clubs that sign on to this strategy, the less effective it's going to be for everyone. Wave of the future? To me, this seems more like a ripple. It's initially disruptive, but destined to settle back to a predictable calm when it proves unsustainable.