In baseball statistics, strikeouts per nine innings pitched (K/9, SO/9, or SO/9IP) is the mean of strikeouts (or Ks) by a pitcher per nine innings pitched. It is determined by multiplying the number of strikeouts by nine, and dividing by the number of innings pitched. To qualify, a pitcher must have pitched 1,000 innings, which generally limits the list to starters. A separate list is maintained for relievers with 300 innings pitched or 200 appearances.

Leaders

Aroldis Chapman was the active leader in 2020 in strikeouts per 9 innings among relievers with over 200 appearances.

The all-time leader in this statistic through 2022 is Chris Sale (11.06). The only other pitchers who had averaged over 10 strikeouts are Robbie Ray (11.03), Jacob deGrom (10.96), Yu Darvish (10.70), Max Scherzer (10.69), Randy Johnson (10.61), Stephen Strasburg (10.55), Gerrit Cole (10.45), Kerry Wood (10.32), Pedro Martinez (10.04) and Aaron Nola (10.02).[1]

The top three in 2022 were Carlos Rodon (11.98), Shohei Ohtani (11.87), and Gerrit Cole (11.53).[2]

Among qualifying relievers, Aroldis Chapman (14.88) was the all-time leader in strikeouts per nine innings through 2020, followed by Craig Kimbrel (14.66), Kenley Jansen (13.25), Rob Dibble (12.17), David Robertson (11.93), and Billy Wagner (11.92).[3][4][5]

In 2022 Kyle Harrison led the minor leagues with 14.8 strikeouts per 9 innings, the highest rate for a pitcher in the minors–minimum 100 innings–in a season dating back to 1960.[6][7]

Analysis

One effect of K/9 is that it may reward or "inflate" the numbers for pitchers with high batting averages on balls in play (BABIP). Two pitchers may have the same K/9 rates despite striking out a different percentage of batters since one pitcher will pitch to more batters to obtain the same cumulative number of strikeouts. For example, a pitcher who strikes out one batter in an inning, but also gives up a walk or a hit, strikes out a lower percentage of batters than a pitcher who strikes out one batter in an inning without allowing a baserunner, but both have the same K/9.[8]

References

  1. "K/9IP All Time Leaders". Baseball-Reference.com.
  2. "Year-by-Year Top-Tens Leaders & Records for Strikeouts per 9 IP". Baseball-Reference.com.
  3. "K/9IP leaders, minimum 200 appearances". Baseball-Reference.com.
  4. "K/9IP leaders, minimum 300 innings pitched". Baseball-Reference.com.
  5. "Rob Dibble Statistics". Baseball-Reference.com.
  6. "Top Pitching Prospects | Left-Handed". MLB.com.
  7. "Kyle Harrison Stats, Fantasy & News". MLB.com.
  8. James Gentile (October 8, 2012). "Stop using K/9 and BB/9!". Beyond the Box Score. SBNation.com.


This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.