ME: This is a great place to start this week. The "opener" is simply a way of kind of inverting the process of how teams handle the first six innings or so of games. The idea is to bring a reliever in to pitch the first inning or two against the biggest threats in the opposing lineup. It is supposed to help supplement the back end of a starting rotation where weaker links typically pitch and where often the stuff is marginal.
The idea: Start the game with a power reliever capable of pitching an inning or two against the biggest threats in the opposing lineup and then you give your "primary" pitcher (the guy with the starter profile) a chance to face more hitters before having to face the best hitters in a lineup a third time.