If you zoom in far enough, the laws of classical physics break down. Gravity is a wonderful tool if you want to understand (inter alia) how the planets move, but produces nonsensical results when tasked with explaining the behavior of photons or quarks. To understand that, you need rather a different approach. Physics, thus, has two toolboxes with which it approaches the world: the “big” physics of Newton, and the “small” physics of quantum mechanics. Depending on the scale of the problem under consideration, one or the other is more appropriate for use.

I bring this up only because of what Jake Arrieta did in Cincinnati last Thursday. While this is hardly the first week during which Arrieta’s performance has given fans cause to reflect upon the deeper questions of life, his decision—and it was nearly as simple as that—to no-hit the Reds in their own house has thrown one particular question back into the spotlight. Namely, this one: Who is the best pitcher in baseball? And that question, like those of physics (if only in this particular way), returns very different results depending on the period over which it is asked.

One particular strain of answer goes something like this: Clayton Kershaw is the best pitcher in baseball, because he’s been nearly as good for the last X time units as Arrieta has been for the last Y, where X is greater than Y. Another, like this: Arrieta is the best pitcher in baseball, because for the last Z period, he’s been better than Kershaw over the same time. (A third strain argues that Chris Sale or Noah Syndergaard, and not Kershaw or Arrieta, is the best pitcher in baseball, but let’s take our cue from ESPN and ignore that line of thinking for the moment.) The important thing is not what value we assign to the variables; the important thing is that the variable represents time.

So, instead of trying to litigate one value for X over another for Y, when both are expressed in terms of years, let me take this in a little bit of a different direction. Let me try to work out, for every moment that baseball was played last Thursday—the day Arrieta threw his no-no—the best pitcher in baseball.


Clayton Kershaw. 12:09 pm ET. Matt Wisler begins throwing against the Los Angeles Dodgers. He’s on the mound, but the best pitcher in baseball, Clayton Kershaw, is sitting in the dugout for the other team. Yes, Kershaw is better than Wisler at this moment, because even though Wisler was technically pitching, both were loose and ready to go. Plus, both gave up a run in the first, so you have to defer and give the title to the guy who walked one and struck out ten in his start (Kershaw) rather than the guy who walked two and K’d just six.

Clayton Kershaw. 12:09 pm ET—approx. 2:57 pm ET. Various pitchers begin throwing in games across the league: Nate Karns and Cody Anderson in Cleveland, Tom Koehler and Max Scherzer in Miami, David Price and Jake Odorizzi in Boston, Taylor Jungmann and Ricky Nolasco in Milwaukee, Jered Weaver and Jordan Danks in Chicago, and Johnny Cueto and Shelby Miller in San Francisco. On a normal day, Price and Scherzer might have a case to claim the throne from Kershaw at some point during this time period, but Kid K was dealing, and both Price and Scherzer were off their games, giving up 8 and 5 runs, respectively. So Kershaw retains his title throughout this period.

Clayton Kershaw. Approx. 2:57 pm ET—approx. 2:58 pm ET. Now, things become a little interesting. Kershaw was lifted after eight innings of one-run ball. At that moment, was he better than Jake Arrieta, who had yet to do his pre-game warmups? I’m gonna say yes, because we know from published reports that Arrieta had a terrible bullpen session on Thursday. So, for another minute, Kershaw holds on.

Matt Belisle. Approx. 2:58 pm ET—approx. 3:32 pm ET. But, at that very moment, other games were still ongoing around the league. Nobody in the Boston-Tampa slugfest qualifies for the Best Pitcher title, and the Mariners-Indians 10-7 final probably doesn’t have any worthy contenders either. But at about 2:58, Matt Belisle took the mound for the Nationals in Miami, and proceeded to throw two shutout innings against that hapless club. After eight innings of his own, I’m guessing Kershaw was gassed, and so I’ll take Belisle for this period.

Matt Belisle. Approx. 3:32 pm ET—approx. 4:45 pm ET. A few games were still being played at this point, but all the pitchers in them started to suck in the late innings; in San Francisco, Cory Gearrin gave up three runs in the ninth. In Chicago, both teams allowed runs in the ninth. So we’ll give the title to a tired Matt Belisle, yet again. I suppose the case could be made for Kershaw still being a better bet to pitch at this point, but he was very tired, I’m sure, and his arm had probably started cramping up by this point in the afternoon.

Gerrit Cole. Approx. 4:45 pm ET—6:15 pm ET. This is a dead zone, with no games being played across the league. Gerrit Cole would start for the Pirates at 6:11, though, and he threw a dandy—six innings, no runs, no walks, seven strikeouts—so let’s give the title to him during this period, when he was some combination of the best pitcher and the most prepared pitcher. If called upon, I’m sure he could have started pitching at 4:45 and been the Best Pitcher in Baseball. He’d have been better than me, anyway. I’m sure there were moments—seconds, even—during this period, wherein he wasn’t, and someone else had just snapped off an excellent slider in their bullpen session, but finding a way to divine which pitcher was better during any one of those micro-moments is beyond my ken. Let’s move on.

Edinson Volquez. 6:15 pm ET—7:08 pm ET. Cole pitched very well, sure, and he’s definitely a better pitcher over the long run, but Volquez was just a bit better, over the course of this particular night night, and he started throwing at 6:15, just a few minutes after Cole. And so it is that we come to Edinson Volquez to bridge the period between then and the moment in which Arrieta started to throw against the Reds, which was at 7:08 pm eastern. The rest is history.


“I regret,” said Nathan Hale, “that I have but one life to give for my country.” I feel a similar thing, but about this piece. I wish, for the benefit of overthinkers everywhere, that I had the energy to break this thing down even further, to get it down to the second—the microsecond, even—and understand at each and every moment of life who, precisely, is the Best Pitcher in Baseball Right Now. But I can’t do that, sadly, because I have limited energy and at some moments, surely, every pitcher in the game is asleep and thus unable to pitch at all. But then, maybe some are better than others at waking up fast and throwing on their cleats, and maybe …

Thank you for reading

This is a free article. If you enjoyed it, consider subscribing to Baseball Prospectus. Subscriptions support ongoing public baseball research and analysis in an increasingly proprietary environment.

Subscribe now
You need to be logged in to comment. Login or Subscribe
I think the "right now" modifier simply means that if all things are equal in regards to rest, injuries, opponent, and preparedness, who would you take in a game right this very second. I'd still take Kershaw.
So Gio Gonzalez started on Friday.... but he could have pitched Thursday on short rest. He's better than Belisle. And Papelbon was in the bullpen and presumably available. So what does "in" really mean? If it means "actively pitching" than a tired Kershaw whose game is over doesn't factor into the discussion, does it?

The possibilities are endless :)