Figure 1. MLB Percentage of Starts by Different Pitchers in Consecutive Games

Figure 1. MLB Percentage of Starts by Different Pitchers in Consecutive Games. Includes League Alliance teams, 1877, and th IA and NA from 1877 to 1880. Taken as a percentage of league starts, ROT numbers reveal five different eras of rotation use. The four man remained a tool of the major league manager until free agency, and has not seen significant use since the 1999 Philadelphia Phillies collapse. (FRANK VACCARO)

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