Thanks to injuries, Aaron Cook wasn't quite himself at the end of his career with the Rockies. In his last 224 innings, over 2010 and 2011, the right-hander displayed an unusual lack of control that tipped the already gentle balance between his strikeouts and walks in favor of the opposition, leading to an ERA+ of just 84 after a four-year stretch at a well-above-average 116.
This earned Cook a spring-training invitation and minor-league deal from the Red Sox, where he would get the opportunity to hook up with the pitching coach who, in Cook's eyes, helped make him into the successful hurler he was in Colorado. You see, Cook has always had great stuff; it just wasn't strikeout stuff. Bob McClure was supposedly the tool that sharpened Cook's approach, the one who made him realize that pounding the lower portions of the strike zone to induce grounders was the way to utilize his stuff.
It's not for lack of stuff that Cook fails to miss bats, it's due to that differing approach. If you're looking to understand that, look no further than Cook's ground-ball rates with the Rockies, earned from a sinker so heavy, you'd swear gravity worked differently for it. Cook didn't luck into the 1,000-plus innings of better-than-average baseball he pitched a mile above sea level. He was built for defying that environment, and until his health failed him, that's just what he did for eight years.
The Cook now pitching for the Red Sox isn't exactly the old iteration of the right-hander. He didn't strike out many hitters out back then, but there still were some punch-outs. At his best, Cook struck out 3.9 batters per nine, a rate he got away with thanks to grounder rates closer to 60 than 50 percent, as well as a Colorado Rockies defense that was more help than hurt to their pitchers. He also limited his walks, with just 2.3 per nine. Everything else was still there for Cook in 2010 and 2011, but the walks were more prevalent, the pitches less under his control, and it cost him.
This Cook, the one the Red Sox have thrown out on the mound five times in 2012, neither misses bats, nor misses the strike zone. Cook has thrown 67 percent of his pitches for strikes, 18 percent of those looking. He's allowed the same number of walks as home runs, and struck out the same number of batters as both of those. You might think that an adjusted-run estimator like fielding-independent pitching would frown on an even K/BB and the lack of strikeouts, but thanks to his seeming inability to issue a walk, Cook's FIP is actually a tasty 4.01.
The ball has been on the ground, his pitches in the strike zone, and that's just where Cook needs to be to survive.
Cook has two "streaks" of starts without logging a strikeout, as he didn't whiff anyone in his first two starts, then struck out two Mariners in his complete-game effort against Seattle*, then followed that up with two more strikeout-less contests. It might seem like this happens all of the time -- and it does -- but lengthy streaks without strikeouts tend to be short, and also full of runs and walks. Cook, to his credit, owns a 4.78 ERA during his pair of two-game, strikeout-less streaks, which sounds poor, but in a relative sense isn't. Plus, in one of those, Cook was still pitching after suffering that gash in his knee that required 11 stitches to close, the one that sent him to the DL for an extended period of time, and nearly all of the runs in those four starts came from just that one game.
*Honestly, though, do strikeouts against Seattle even count? Between you and me, Cook has five straight starts without a strikeout.
Pat Hentgen has the longest streak of starts without a strikeout during the wild card era (1994 through 2012), when he went four-straight without a punch out back in 2004. Hentgen gave up 25 runs, walked 16, and managed just 12 frames over those four starts. All of a sudden, Cook's 4.78 ERA in his own runs looks pretty wonderful.
Cook's four starts without a strikeout are also the most by a Red Sox pitcher since 1998, when Bret Saberhagen, in his 175 innings, squeezed in five starts sans strikeout. It's just not something you see often, since pitchers who fail to miss bats at all generally also fail to stick in the bigs for very long, or, at least, while maintaining that kind of approach and results.
To say this kind of run is rare is putting things mildly. Just three pitchers ever have finished their season with at least 29 innings pitched (as Cook has), and less than one per nine of both strikeouts and walks -- one of those, generously, is Cook, whose season is far from over. That basically leaves us with two: Jake Norththrop, in 1918, who threw 40 innings with a 0.9 K/9 and 0.7 BB/9, and the 1919 version of Slim Sallee, who threw 227 innings with a strikeout rate that hits an even 1.0 only if you round up, along with 0.8 walks per nine.
Sallee finished the 1919 campaign with a 136 ERA+, good for 12th best in the majors out of 68 pitchers who qualified for the ERA title that year. "Scatter" Sallee had an appropriate nickname, as he scattered hits for 14 years, finishing his career with a 114 ERA+, despite strikeout rates that even for the time looked paltry in comparison to the averages. Like with Cook in 2012, Sallee's thing was limiting walks: from 1916 through the end of his career, in 1921, Sallee never walked more than 1.9 hitters per nine, and, all told, posted a 1.2 mark over those last 986 innings and 175 games.
Cook has a long way to go to pull off what Scatter did, but he's been successful, even in a short burst, where so many others have failed over the years. Something like this could end at any time, so appreciate weird baseball, courtesy of Aaron Cook, while you can.
Thanks to Baseball-Reference's Play Index for the historical nuggets.