In Major League Baseball, the 3000 strikeout club is an informal term applied to the group of pitchers who have struck out 3000 or more batters in their careers. The club's "founding member" was Walter Johnson in 1923. He was the only pitcher to have reached this milestone until Bob Gibson recorded his 3000th strikeout in 1974. Since then, twelve more hurlers have joined the club. This recent increase may be explained by the existence of more free-swinging hitters than before, corresponding with an increase in the number of home runs. Nevertheless, 3000 strikeouts remains a very notable feat, as there are only 14 members of this elite corps.