The Triple Crown of pitching is "awarded" to the pitcher who leads — or ties — his league in three major pitching areas: 1: wins, 2: strikeouts, and 3: earned run average. All three of those categories must be led or tied at the end of the season in order to be part of a Triple Crown performance. Few pitchers have ever come close and when one simply leads in two categories it is often a noteworthy achievement. Baseball Almanac is pleased to present the Triple Crown Winners.
"I have it figured out. Pitcher's aren't going to like the answer I give, but it's true, and it is in four short words. They aren't ball players." - Vance, Dazzy. National League Triple Crown Winner (1924). The Sporting News. 14 August 1957. Page 24.

In 1884, Guy Hecker, who played for Louisville Colonels of the American Association, also earned the Triple Crown (the second in Major League history) and is the only American Association pitcher to do so during their history. He had 52 wins, 385 strikeouts, and an earned run average of 1.80!
More than one-hundred forty years of Major League Baseball seasons played, thousands of great pitchers, and the Triple Crown has only been earned forty-one times by thirty-one different Major League pitchers!
The MLB Triple Crown of Pitching
The MLB Triple Crown of pitching takes place when the pitcher's win total, strikeout total and ERA are not just the highest in their respective league, but the highest in Major League Baseball, across both leagues. They are the literally the pitcher with more wins than any other pitcher, more strikeouts than any other pitcher, and the best earned run average in all of baseball during the season.
Pitchers who earned the MLB Triple Crown of pitching are: Walter Johnson (1913), Grover Alexander (1915), Walter Johnson (1918). Dazzy Vance (1924), Lefty Grove (1930), Lefty Grove (1931), Hal Newhouser (1945), Sandy Koufax (1963), Sandy Koufax (1965), Sandy Koufax (1966), Dwight Gooden (1985), Johan Santana (2006), and Shane Bieber (2020)!
Koufax is King: From that incredible list (MLB Triple Crowns) above, the only pitcher in the entire history of baseball listed three times is Sandy Koufax. And for added context, just three pitchers total have achieved the MLB Triple Crown since!
Grover Alexander (1915 & 1916), Lefty Grove (1930 & 1931), Sandy Koufax (1965 & 1966), and Roger Clemens (1997 & 1998) each accomplished a triple crown in pitching in consecutive years.