Baseball is somewhat of an outlier among American sports in that the game-by-game strategy for personnel usage changes drastically when the postseason begins. Most notably, pitcher usage shifts dramatically, with the best and hardest-throwing pitchers working nearly every single important inning in October. The game slows down, and offense is typically at a premium.
Part of the impact of the shifts in October is a renewed emphasis on pinch-running. Teams rarely utlize pinch-runners outside of obvious spots during the regular season, typically opting to keep their best bats in as long as possible. But with so many high-leverage spots in October which feature a team trying desperately to tally just a single run, pinch-running often takes the spotlight.