Gooden suffered a shoulder injury in 1989, which reduced him to a 9–4 record in 17 starts. He rebounded in 1990, posting a 19–7 season with 223 strikeouts, second only to teammate David Cone's 233. However, after another injury in 1991, Gooden's career declined significantly. Though drug abuse is commonly blamed for Gooden's pitching troubles, some analysts point to his early workload. It has been estimated that Gooden threw over 10,800 pitches from 1983 to 1985, a period in which he was 18 to 20 years old. Gooden hurled 276 innings in his historic 1985 season; as of the end of the 2017 season, only two subsequent pitchers have thrown that many innings (Charlie Hough, a knuckleballer, and Roger Clemens, both in 1987). By the time he reached his 21st birthday, Gooden had already accumulated 928 strikeouts between the minor and major leagues.