This countdown is a way for me to look back at the three decades I've spent as a baseball fan. My introduction to the project, with an explanation of sorts, and links to every entry can be found here.
Since the end of the Dead Ball Era, exactly two other pitchers have had a seven-year stretch with such a low ERA (minimum of 1200 innings): Greg Maddux from 1992 through 1998 posted a 2.15 ERA, and Clayton Kershaw during the last seven seasons posted a 2.18 ERA. That's it. Maddux started his run before offense exploded Kershaw had his run after the offensive peak had passed. Both of them pitched all seven of those seasons in the National League, an easier task for pitchers (in large part due to the absence of a DH). Pedro posted his entire run during the peak decade for offense in Major League history, and six of his seven seasons came in the American League, pitching his home games at hitter-friendly Fenway Park. During those seven years, Maddux and Roger Clemens were the only other pitchers to have a single season with an ERA as low as 2.20. They each did it once; Pedro averaged it for seven years. He struck out the second-most batters per inning during that time, and gave up the second-fewest home runs per inning, while also placing in the top ten for fewest walks per inning.
ERA+ accounts for era and ballparks. Kershaw's ERA+ during the last seven year: 170. Fantastic. Maddux's ERA+ during his run: 190. Otherworldly. Pedro's ERA+ during his run: 213. My vocabulary isn't impressive enough to put an appropriate word to that.
In the year 2000, Pedro pitched 217 innings and had an ERA+ of 291, the highest in baseball history for a starting pitcher. If you believe ERA and ERA+ are flawed tools for measuring a pitcher because they include things somewhat outside his control, such as the quality of the defense behind him, and you prefer to use FIP instead, then the best season since the Dead Ball Era belongs to... Pedro Martinez, who had a FIP of 1.39 the year before, in 1999, when his ERA+ was 243, only the fifth-best figure since the Dead Ball Era.
Cable television and Martinez joining the very popular Red Sox combined to make most of those seven years much easier to follow than almost any non-Chicago pitcher had been during my life to that point, and when the game itself wasn't available for viewing, Pedro would often be the lead story on Baseball Tonight, making it easy to see the highlights. Starting in 1994, I always went to Comiskey to see the Indians when they were in town, and to Wrigley if Maddux was going to be pitching. Pedro became another "I have to be there" for me; I saw him start in Chicago three or four times, and once in Boston.
The Pedro game that stands out the most for me wasn't a start. In Game 5 of the 1999 ALDS the Indians faced the Red Sox in a win-or-go-home matchup. The Tribe scored eight early runs. Then Pedro entered from the bullpen. I watched in a mix of horror and awe as he pitched six no-hit innings against my favorite team. Those Indians are the only MLB team in my lifetime to have scored 1000 runs in a season; Pedro annihilated them.
Martinez's last great season came when he was 33, and his last game came only days after he turned 38. His career counting totals are impressive, but not nearly the same way as those of some of the other guys on this list. Because of all that, I can't rank him any higher than this, but I've never seen anyone pitch any better than peak Pedro.