Major league pitchers beating all 30 teams

Since 1998, there have been 30 teams in Major League Baseball (MLB). It is very rare for a pitcher to record a win against every team. In earlier times, two factors made it nearly impossible to defeat all teams in both leagues (even before expansion increased the number to 30):

In any case, defeating all teams is more likely only if a pitcher has a long career. Assuming a top notch pitcher manages to win against every team in a season, it will still only be 19 teams, unless he was traded. It is far more likely that his wins will come against 10 to 12 teams, most of which he has already beaten.

As of August 20, 2017, there have been 18 pitchers who have beaten all 30 teams. The San Francisco Giants are the only franchise with three players who accomplished the feat while on their roster: Randy Johnson, Barry Zito, and Tim Hudson.

As of August 20, 2017, nine active pitchers have defeated 29 teams.

As of January 16, 2017, four active pitchers have defeated 28 teams.

As of January 16, 2017, three active pitchers have defeated 27 teams.

As of January 16, 2017, the following active pitchers have defeated 26 teams.

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