Is a good closer really that important?

The closer is the most important pitcher in the postseason. The starting pitchers are for the regular season. It is statistically true that the teams who have their starting pitchers make it through the 7th inning the most in the regular season are those who move onto the postseason. Why? Because the bullpen isn't depleted. Relievers are your "first responders". They're always on duty and are usually your hardest throwing pitchers. These guys throw so hard, that their arms can't take more than 2 innings. They are their to shut down any situation. You don't want a starter who's thrown 100 pitches to blow game 7 of the World Series with a walk. Closers come in and throw the heat, starters pick places with curve, change ups, knuckle, etc. Closers = Fastball, Slider.