Can Jake Arrieta Keep This Up? Data, Instead of History, Might Hold The Answer

This much we know for sure: Thursday night in Cincinnati was not Peak Jake Arrieta. The Cubs’ ace did complete his second no-hitter in less than eight months, shutting out the Reds in a 16-0 rout, but he walked four batters, fanned only six, and needed nearly 120 pitches to do it. Compared even to his complete-game shutout of Cincinnati at Wrigley Field back in September of 2014, this was a routine, even a somewhat underwhelming outing. Arrieta has been better and more dominating (often, against better offenses) a fistful of times over the last two years (see Ryan Davis’s post today for more on this). It’s a testament to the stretch Arrieta has enjoyed that a no-hitter can feel so little like a new mountaintop.

Indeed, it’s getting hard to imagine that there are more mountaintops for Arrieta to summit, that he can really keep this up any longer. Thursday made him just the 11th player since World War II (and eighth of the divisional era) to help his team to a win in 17 straight starts, and of the players who have managed such streaks, Arrieta’s is by far the most impressive. Thursday’s was also Arrieta’s 24th consecutive Quality Start, which is two shy of Bob Gibson’s record (he had 26 straight starts meeting the official criteria for this statistic, from late 1967 through late 1968), but really, should already be the record—Gibson’s streak included a couple of starts in which he allowed more than three runs, but some were unearned.

Let’s widen the scope a bit, and look at the whole body of stellar work Arrieta has done since fully tapping into his talent. To do so, we have to go all the way back to June 2014. Arrieta had gotten a late start to his season after some shoulder soreness in camp, and didn’t find his groove until a June 8 start. Using the game he pitched that day as a starting point, Arrieta’s last 56 starts look like this:

Jake Arrieta, Since June 8, 2014

Starts Quality Starts Innings ERA Batters Faced Strikeouts Walks Opp. AVG Opp. OBP Opp. SLG
56 50 386.2 1.89 1,457 401 82 .180 .230 .264

I set out to find pitchers who have been similarly dominant over a stretch this long, at any point during the last decade and change, and came up with a few pitchers who loosely fit Arrieta’s career arc (either in that they bloomed late, or in that they went through substantial adversity before finding success), in addition to roughly matching the duration of his dominance. Here are Jason Schmidt’s numbers over 62 starts, from late 2002 through late 2004:

Jason Schmidt

Starts Quality Starts Innings ERA Batters Faced Strikeouts Walks Opp. AVG Opp. OBP Opp. SLG
62 45 442.1 2.48 1,759 468 130 .196 .256


Here’s Johan Santana, over the last 22 starts of 2004 and all of 2005:

Johan Santana

Starts Quality Starts Innings ERA Batters Faced Strikeouts Walks Opp. AVG Opp. OBP Opp. SLG
55 45 391 2.26 1,493 442 76 .186 .230 .305

And here’s Justin Verlander’s run of dominance, from late 2010 through early 2012:

Justin Verlander

Starts Quality Starts Innings ERA Batters Faced Strikeouts Walks Opp. AVG Opp. OBP Opp. SLG
54 43 388.1 2.34 1,502 392 81 .191 .237 .302

Each of these pitchers had something close to the mileage Arrieta had on his arm when he began his ascension to the apex of pitching performance. Each was at least close to his age. (Santana, I must note, was meaningfully younger, though he’d been a professional pitcher about as long.) Each also declined irreversibly, as it would turn out, at the end of these stretches of dominance. Santana and Verlander each enjoyed strong seasons, or parts of seasons, after these peaks, but neither was their transcendent selves again for a prolonged period. Perhaps the length of their respective turns as the game’s preeminent starter suggest that Arrieta is getting close to the end of his own.

Then again, maybe not. Here’s one more comparison, to the one pitcher who might still be better than Arrieta.

Clayton Kershaw, July 29, 2012 Through End of 2014

Starts Quality Starts Innings ERA Batters Faced Strikeouts Walks Opp. AVG Opp. OBP Opp. SLG
72 62 521.2 1.76 1,991 564 108 .194 .237 .283

Kershaw was, at his best, at least as good as Arrieta has been. He can’t match Arrieta’s result numbers, but he sustained superlative performance for longer than Arrieta has, at least to this point. He also had a higher strikeout rate throughout that peak, and about the same walk rate. And then, arguably, Kershaw got even better last season.

Clayton Kershaw, 2015

Starts Quality Starts Innings ERA Batters Faced Strikeouts Walks Opp. AVG Opp. OBP Opp. SLG
33 27 232.2 2.13 890 301 42 .194 .237 .284

We’ve reached the point, then, at which we have to decide whether we think Arrieta is a normal, human pitcher, or Clayton Kershaw. If the former, we should expect him to decline soon. He’ll still be a solid, top-of-the-rotation starter, but he’ll wear or break down, or his stuff will simply soften, or the league will find the adjustment it’s been searching for for going on two years—namely, one that will work. If the latter, there might be another level, another gear as yet unexplored.

Of course, that’s a false choice. It’s true that Kershaw is an historical outlier without good historical precedent, but there’s no reason to corner ourselves into believing that if Arrieta isn’t Kershaw, he can’t be his own outlier. Indeed, I suspect that’s exactly what he is. Let me offer some supporting evidence.

Of the 187 pitchers who have allowed at least 200 batted balls tracked by StatCast since it came into being, Arrieta has allowed the lowest average exit velocity (85.2 miles per hour). Immediately trailing him on that leaderboard are Kershaw, Noah Syndergaard, Dallas Keuchel, and Francisco Liriano. Among the same set of pitchers, Arrieta has allowed the third-lowest average batted ball distance (trailing only Keuchel and Aaron Sanchez), thanks to much higher ground-ball rates than, for instance, Kershaw. Eleven of the 19 balls the Reds put in play on Thursday night were grounders, indicative of ongoing progress Arrieta has made in that area.

StatCast podcast host Mike Petriello tracks a stat for hitters he calls “Barrels.” A Barrel is any batted ball hit at least 100 miles per hour, at a launch angle between 10 and 30 degrees. They’re named because those vital statistics indicate that a ball was really barreled up, and they tend to end up as hits (often for extra bases). In 2015, the only starters who allowed Barrels on a lower percentage of their pitches than did Arrieta were Kershaw, Syndergaard, and Tyson Ross. Keuchel, Carlos Martinez, and Matt Harvey were among the names right behind Arrieta in avoiding Barrels. Of those six pitchers, though, not one allowed as low an average exit velocity or as low an average distance on Barrels as did Arrieta. In other words, even when hitters square him up, Arrieta seems to have a knack for missing the sweet spot by a fraction of an inch. That (again, along with the ground-ball rate) helps explain Arrieta’s minuscule home run rate, his biggest advantage over Kershaw.

FanGraphs has helpful data from Inside Edge, breaking down batted balls in a more qualitative way. They break out the direction in which balls are hit (Pull, Center, Opposite), and subjectively grade the quality of contact on every batted ball allowed (Hard, Medium, Soft). Arrieta’s splits are fascinating. Since the start of 2014, of the 112 pitchers who have thrown at least 250 innings, Arrieta has allowed opposing hitters to pull the fifth-fewest (24.3 percent of them). That’s strange for a ground-ball guy, since most hitters pull most of their grounders. He also ranks third in the percentage of opponent batted balls graded as Soft contact, at 22.9 percent, trailing only Keuchel and Francisco Liriano. As I’ve documented before, both of those pitchers thrive by aiming below the strike zone a huge percentage of the time. They create soft contact (and get their swings and misses) by luring hitters into chasing below the knees. Arrieta does things very differently. He was just above the median in percentage of pitches in the strike zone last year, and this season, he’s pouring it into the zone even more regularly. He’s able to generate weak contact and bad swings without nibbling, in a way no other pitcher can.

To all of that, you can add Arrieta’s Pilates-carved physique, that unique and deceptive delivery (the crossfire pattern, the pat of his glove with the ball just before really exploding toward the plate; that’s perhaps where he and Kershaw most nearly cross paths), and the easy way Arrieta has set opponents down this season. He’s throwing his slider less often, his sinker way more often, and seems to refuse to strain himself all that much. Even in approaching 120 pitches on Thursday, Arrieta looked not only comfortable, but smooth. He seemed to consciously ease off the gas pedal.

A little over 62 percent of Arrieta’s pitches over the first five innings were sinkers, but in innings six through nine, that number was 73 percent. That not only allowed him to be efficient (45 pitches in the four frames, after 74 to get through five), but made the pitch count almost irrelevant. Arrieta wasn’t pressing. He wasn’t laboring. Hilariously, and forgivably, since the game was way out of hand, he barely seemed to be trying. He pounded the zone with sinkers, finished no-hitting a big-league team, and celebrated with his teammates. Time will tell whether the Cubs will protect Arrieta the way they need to, and whether Arrieta can so consistently rely on the low-stress sinker going forward. If he can, though, and given the good health his training regimen should encourage, I think Arrieta can be more than Verlander, Santana, or Schmidt, better than Felix Hernandez or Chris Sale. He doesn’t have Kershaw’s strikeout totals or Syndergaard’s velocity, but it seems like Arrieta has a genuine chance to share Kershaw’s staying power, and put his name alongside some of the game’s modern pitching greats.

He just has to be a lot sharper than he was Thursday.

Lead photo courtesy David Kohl—USA Today Sports.

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1 comment on “Can Jake Arrieta Keep This Up? Data, Instead of History, Might Hold The Answer”


Great stuff, Matt! You threw out some stats I’ve never even heard of there, and I love it! Barrel stat? That sounds like something worth keeping an eye on moving forward.

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