If the "save" statistic never existed, the idea of "saving" your best pitcher wouldn't be a thing. Managers don't "save" their best starters for later games in a playoff series. They want their starters in as many games, in as many high leverage situations as possible. Your best bullpen guy should be used in a key, high leverage situation, regardless if that situation is in the 7th, 8th or 9th and regardless if you have the lead or are tied or winning.