The 2017 strikeout-to-walk leaderboard is filled with some of the Majors' most dominant, least hittable arms. The ability to rack up strikeouts without issuing free passes is, after all, the hallmark of an elite pitcher -- someone who has the stuff to mow hitters down and the command to match.
Consider some of the names in this category. They are pitchers with long track records of success, some of them among the best of this generation. This list includes Clayton Kershaw, Jeff Samardzija, Corey Kluber, Max Scherzer, Chris Sale and Zack Greinke, most of whom led the pitching staffs of teams that dominated the competition throughout the regular season.
Not only that, but four of those aces are Cy Young Award winners. Greinke took home the hardware with the Royals in 2009. Kershaw has won the NL Cy Young three times, in 2011, '13 and '14, and in the latter campaign was also the Senior Circuit's Most Valuable Player. Kluber became the AL Cy Young recipient in 2014. Scherzer is the NL's reigning Cy Young Award winner and has earned the award in both leagues, having first won in the AL with the Tigers in 2013.
"Strikeouts are part of my game," Scherzer said after recording the 2,000th of his career in June. "I'm looking to generate strikeouts in every way I can. It's about how you throw finishing pitches in the at-bat, trying to dissect hitters to figure out how to increase [strikeouts].
"But I try to do it efficiently. I'm not trying to throw six or seven pitches just to be able to strike you out. I'm trying to do it in three or four."
In bullpens across the Major Leagues, you'll find more of the same. Relievers do not generally throw enough innings to qualify for the strikeout-to-walk ratio title, but in their short bursts, they are often among the most skilled at sending hitters back to the dugout while making teams work hard for the few base runners they can manage to scrape together.
In 2017, Kenley Jansen stood out in particular. The Dodgers' closer didn't allow a walk until June, while striking out 51 of the first 112 batters he faced. Until that point, his K/BB was literally undefined. Through the regular season, he averaged 15.57 strikeouts for every walk, issuing just seven total free passes. Jansen, who recorded a 10.00 and 9.45 K/BB in the last two seasons, respectively, was head and shoulders above the next-closest relievers, Colorado's Pat Neshek and the Red Sox's Craig Kimbrel, who was brilliant in his own right, with a ratio of 14 walks to 126 strikeouts over 69 innings (10.00 K/BB).

After anchoring the Dodgers' bullpen deep into last year's playoffs, Jansen brought his game to another level while joining some elite company. Heading into the 2017 campaign, Hall of Famer Dennis Eckersley, who posted an 18.33 K/BB in 1989 and an 18.25 a year later, owned the first two spots on the best single-season K/BB list for relievers.
"I definitely got to know myself," Jansen said. "I threw 2 1/3 innings in the clinching game [against Washington in the 2016 NLDS], three innings against the Cubs [in the NLCS finale], stuff I never did. You just feed off it and get better, and you want to know how good you can be."
The single-season K/BB record for a starting pitcher, for all intents and purposes, should belong to Kershaw. What Jansen did this season, his teammate did in 2016. Last year, in arguably one of the most amazing stretches a starter has ever put together, Kershaw struck out 172 batters and walked just 11 for a 15.64 strikeout-to-walk ratio. The fact that he has to throw far more innings than a closer only makes what he did even more incredible.
The only thing keeping him out of the official record book is the fact that a back injury limited him to 149 innings pitched, about 13 short of the 162 necessary to qualify. But lower the bar just slightly, and Kershaw's would be the best single-season K/BB mark of all time for a starting pitcher in the modern era.
"Walking guys is how you get in trouble," Kershaw said last May, after setting an MLB record: five consecutive starts with at least 10 strikeouts and no more than one walk. "I'd rather them string hits and make them swing bats to beat me; that's always my mentality. You want them to [have to] beat you. I attack them."
Saberhagen posted an 11.00 K/BB ratio for the Mets in 1994. Lee finished at 10.28 in 2010, when he split time between the Mariners and Rangers. Schilling's K/BB was 9.58 for the Diamondbacks in 2002. Pedro's best marks came in his historically great 1999 and 2000 campaigns; he struck out 313 and walked just 37 in '99 (8.46 K/BB), and had 284 strikeouts to 32 walks the next year (8.88 K/BB). Maddux, the Braves' master craftsman, struck out 8.85 batters for every walk he issued in 1997. Sheets's K/BB was 8.25 for the Brewers in 2004, and Scherzer's was 8.12 for the Nationals in 2015.
Including the moundsmen in that group, 20 starting pitchers in MLB history (through the 2017 regular season) have posted a single-season K/BB ratio of 7.00 or higher. The names don't get any less illustrious. Maddux, Schilling and Lee all come up again. Kershaw surfaces twice. Roy Halladay, David Price, Fergie Jenkins and even Cy Young himself all make appearances.
When it comes to the postseason, a staff led by a high strikeout-to-walk ratio is a key component of the formula for a club's success. The pitchers who limit base runners are tremendously valuable. Nothing reflected that like the career K/BB leaderboard through the 2017 regular season. Among the top hurlers behind Sale were Kluber, Schilling, Madison Bumgarner, Kershaw, Pedro, Mariano Rivera and Scherzer. These are the superstars of perennial playoff contenders, and some of the most storied postseason performers in recent history.
Bumgarner, Schilling and Rivera are three of the best postseason pitchers ever. Bumgarner owns three rings, is 8-3 with a 2.11 career postseason ERA, and turned in one of the most awe-inspiring efforts in Fall Classic history against the Royals in 2014. Schilling went 11-2 with a 2.23 ERA in his playoff career, won three championships of his own, was the 2001 World Series MVP for the D-backs, and helped the Red Sox shatter the Curse of the Bambino in 2004. Rivera, the greatest closer ever and one of the cornerstones of the Yankees dynasty, built his legacy in October: 42 saves in 96 career playoff appearances, on his way to five World Series titles with New York.
Whether or not the likes of Kershaw and Jansen can join the ranks of these postseason greats throughout their careers is yet to be seen. But one thing is for sure: Fans will be on the edge of their seats -- and batters will be sent back to theirs -- as they try.
This article appears in the World Series Program. To purchase a copy, visit mlbshop.com.