Page "History of baseball in the United States" Paragraph 48

Routinely in today's baseball age we see players reach 40 and 50 home runs in a season, a feat that even in the 1980s was considered rare.

Many modern baseball theorists believe that a new pitch will swing the balance of power back to the pitcher.

A pitching revolution would not be unprecedented — several pitches have changed the game of baseball in the past, including the slider in the 1950s and 1960s and the split-fingered fastball in the 1970s to 1990s.

Since the 1990s, the changeup has made a resurgence, being thrown masterfully by pitchers such as Tim Lincecum, Pedro Martinez, Trevor Hoffman, Greg Maddux, Tom Glavine, Johan Santana, Justin Verlander and Cole Hamels.