MLB: Key to success for all 30 teams heading into 2015

With opening day around the corner, what is that one essential and unique key each MLB team needs to have happen for ultimate success in 2015?

It was as easy as one, two, three for Ned Yost and the Kansas City Royals last October.

Once opponents entered the seventh inning against the eventual AL Pennant winners, they understood the severity of what loomed – the Kansas City bullpen.

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Kelvin Herrera, Wade Davis and Greg Holland weren’t just lights out, they were downright filthy while the lights were out. So good that they became the first pen in history to start a postseason 7-0 (previous best was 2003 Florida Marlins at 7-1).

Yost realized all he had to do was get to the seventh inning, or sometimes even the sixth, with a lead. The rest would take care of itself.

Even youngster Brandon Finnegan started to catch fire.

While Kansas City’s bullpen was only solid in the regular season, ranking 10th with a 3.30 earned run average (ERA), this knee-buckling weapon became the Royals top key to success in 2014.

It turned out to be a critical factor that turned the lowest home run producing team in the majors last year into AL Pennant winners.

This is where baseball becomes fun: identifying that one aspect of a club that will make or break a team’s season.

Listen, there’s no question a lot of factors determine a winner or loser in baseball. Oftentimes many things have to click on all levels for a team to even sniff October baseball.

Still, all 30 MLB teams are molded in a way that there is one very unique and critical key that’ll determine the outcome of so many games. Without the dominance of Herrera, Davis and Holland last year, the Royals would’ve finished as an average to nice story instead of a legendary one.

As we take a look at every team’s top key to success for 2015, we’ll travel through time based on the normal “newspaper” top to bottom standings order, with a worst to first method from a year ago (AL East, AL Central, AL West, NL East, NL Central, NL West).

So, without further meaningless fluff, here we go:

Next: Boston Red Sox