The Tampa Bay Rays and Kansas City Royals have been two of the biggest surprises in Major League Baseball this season and they are both doing it with an unconventional approach to starting pitchers that could soon become the norm.

Despite making it to Game 7 of the World Series a year ago, most expected the Royals to regress in the tough AL Central division, with just three of 88 ESPN.com experts predicting the Royals would win the division this year. Likewise, only one of the 88 experts predicted the Rays to win the East and that was before sending 17 different players to the disabled list at various points this season.

The key to the success of both teams has been an unusually high usage of relief pitchers, or maybe more accurately, a minimized usage of starting pitchers. However, unlike the trend in recent decades of using starting pitchers less in an attempt to avoid injuries, the Rays and Royals are not limiting the number of pitches being thrown, but rather, they are limiting the number of batters the starting pitchers are facing to in order to increase their effectiveness.

This strategy of limiting the number of batters a starting pitcher faces is based on the simple concept that hitters get better the more times they face a pitcher in a game. While an opposing hitter's OPS increases slightly from the first at bat to the second at bat, it shoots way up in the third at bat.

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By recognizing this trend, the starting pitchers for the Rays and Royals lead the American League in the fewest batters faced per start, something never seen by successful teams.

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To put it another way, the Rays lead MLB in pulling starting pitchers with 18 or fewer batters face, that is before the leadoff batter comes up a third time. The Royals are tied for second.

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Of course, fewer batters faced means fewer pitches thrown. The starters for the Royals and the Rays both average fewer than 90 pitches per game. That's a number that would seem absurd to those baseball traditionalists who lament the loss of an era when starting pitchers regularly threw 110+ pitches and 130-140 was not unheard of.

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Again, these are not starting pitchers who are being taken out of games early because they are getting shelled. Rather, they are pitching well and are still being taken out early. These are two of the best pitching staffs in the AL on two teams leading their divisions.

So far in 2015, there have been 209 games in which a starting pitcher has completed fewer than 6.0 innings despite giving up two or fewer runs. Of those, 37 (18%) have been by Rays (25) or Royals (12) starters.

While not addressing the strategy directly, Rays manager Kevin Cash touched on the issue in May after taking starting pitcher Nathan Karns out of a game after five innings against the Orioles despite not allowing a run and giving up just two hits.

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