Chris Archer is the Game’s Best Pitcher by Alex Chamberlain June 17, 2015 When I decided to write this post, I already knew I would investigate which pitchers experience the largest platoon splits. I know this kind of information is helpful for daily fantasy sports (DFS), and I had yet to see someone undertake this task, although perhaps I wasn’t looking hard enough. I would take a relatively simply metric, sure to ruffle the feathers of the nitpicky, and compare its magnitude against lefties to its magnitude against righties for all pitchers. The largest differences between the two rates would warrant my attention. So, too, would the smallest. (Indeed, the absolute smallest would.) However, I got distracted, as I am wont to do. I walk into a grocery store needing bread and milk and leave with paneer, sprouted tortillas, maple bacon Kettle chips and a 32-ounce bottle of sriracha. Really, I get distracted every time I sit down to write, and I rarely write the piece I originally intended to. My point: I get distracted by things. Things like Chris Archer, who seems to be the Major League Baseball equivalent of the The Most Interesting Man on Earth. I planned to discuss the metric in question — K-BB%, to spare you any more suspense — and why, despite its simplicity, I think it’s a perfectly adequate measure of pitcher effectiveness. I planned to explain, for the sake of reiteration, that a pitcher who maximizes his strikeout rate (K%) guarantees as many outs as possible, or, inversely, guarantees as few plate appearances as possible that are vulnerable to the unpredictability of the batted ball. Furthermore, a pitcher who minimizes his walk rate (BB%) guarantees as few automatic baserunners as possible, or, inversely, guarantees as many (non-strikeout) plate appearances as possible that gamble on balls in play instead of accepting the surety of bases on balls. Alas, a pitcher who can optimize each of these rates allows himself a wider margin of error and a greater chance for success. A pitcher who can optimize each of these rates versus hitters of same and opposite handedness further emboldens his chances for success, as he has minimized any weaknesses notoriously observed in platoon splits. K-BB%, therefore, is a satisfactory way to measure pitcher effectiveness without relying too heavily on econometric or statistical rigor. Archer does this. He optimizes, and he optimizes perfectly. The difference between his K-BB% rates versus lefties and righties — what I will henceforth call the platoon split differential — is exactly zero. Zero-point-zero-zero. Archer is not the only pitcher to contemporaneously accomplish this. Johnny Cueto can make this claim. So, too, can Hector Santiago. And more than 20 other pitchers carry platoon split differentials clocking in at fewer than two percentage points. (For clarity: David Price’s K-BB% is 17.0 percentage points versus lefties and 16.4 percentage points versus righties, resulting in a platoon split differential of 0.6 percentage points.) Why is Archer so special, Alex? Why are you burying the lede? Great questions all around. Glad you asked. Archer’s strikeout rate, you see, exceeds his walk rate by more than 25 percentage points — 26.4 percentage points, to be precise — against lefties and against righties. No one else comes close. Cueto, Jacob deGrom and Matt Harvey have notched K-BB% rates a few hairs north of 20 percentage points versus both sides, but realistically, they’re a far cry from what Archer has accomplished. Because I am not nearly SQL-literate enough to navigate FanGraphs’ database with aplomb, I woefully clicked through the platoon splits for all qualified hitters year by year until I could find a comparable name, a name of a pitcher who demonstrated elite K-BB% rates against hitters of all handednesses. Several minutes later, I encountered results, nestled in the 2002 season. The names that I discovered were obscure but recognizable: Pedro Martinez, who notched a 25.3 K-BB% versus righties and a 25.3 K-BB% versus lefties, and Curt Schilling, who recorded a 29.3 K-BB% versus righties and a 26.2 K-BB% versus lefties. You may have noticed that Pedro achieved the exact feat about which I speak to you today: a platoon split differential of exactly zero with K-BB% rates each greater than 25 percentage points. You may have also noticed that 25.3 is less than 26.4 — that is, Archer, irrespective of batted ball outcomes, is achieving at a higher rate than Pedro did in 2002. This caveat, irrespective of batted ball outcomes, carries a lot of weight — weight that I’ll ignore for now — not to mention that Pedro conquered during the most prolific offensive era to grace (or plague) the sport. Regardless, Pedro and Schilling are no slouches, and neither is Archer — at least, I hope he’s not, considering he held his own in a duel of statistical fisticuffs with two Hall of Fame-caliber pitchers. I may have obscured my thesis, so let me revisit the title, albeit with a bit less conviction: Chris Archer may be baseball’s best pitcher at this precise moment. To those who follow and, above all, trust wins above replacement (WAR), this assertion may be less shocking, given he ranks second in WAR behind only Max Scherzer. Archer has effectively neutralized righties and lefties alike, all but eradicating any glaring weaknesses in elite fashion. He optimizes in the truest sense of the word, maximizing his probabilities for success no matter the handedness of his opponent, in ways we haven’t seen since a couple of baseball’s all-time greats did. And he’s minimizing the odds of damaging balls in play in ways even Pedro and Schilling couldn’t achieve, incurring a ground ball rate (GB%) north of 50 percent to go with the game’s third-lowest pull rate (Pull%). If for some reason K-BB% doesn’t float your boat, then I can replace his K-BB% with his weighted on-base average allowed (wOBA), which still ranks in the top 10 versus both sides of the plate. This now accounts for the batted ball outcomes I previously ignored. And if you’re not a fan of wOBA, I can instead use expected fielding independent pitching (xFIP), which controls for the number of home runs Archer has been expected to allow, and he would rank in the top six versus both sides. In May, Owen Watson discussed Archer’s elite slider; Eno Sarris further validated the pitch two weeks ago. A little later in May, Carson Cistulli noted how Archer compared very favorably to some of his decidedly excellent contemporaries. Last week, Dave Cameron, chronicling the evolution of his utterly devastating yet somehow still-developing pitch, deemed Archer unhittable. Like a reel of Chuck Norris jokes, Archer provokes bolder and bolder headlines with every start. So here’s another to add to the list. This time, with conviction: Chris Archer is baseball’s best pitcher.