After finishing below .500 for their ninth consecutive year and out of the playoffs for their 27th consecutive year, the Kansas City Royals decided to try to win now. In the offseason, they traded top prospect Wil Myers (among others) in a deal to acquire James Shields and Wade Davis from the Tampa Bay Rays. In addition, they added Ervin Santana with a separate trade and re-signed free agent Jeremy Guthrie. The moves suggested the Royals believed that an upgraded rotation would help their emerging offense carry them to the postseason.
More than two months into the season, the Royals are again under .500 and in third place in the AL Central, but the offense has been the real letdown as cornerstone players Alcides Escobar and Mike Moustakas have on-base percentages below .270 and Eric Hosmer has just two home runs. The offseason moves to upgrade their pitching, meanwhile, seem to have worked. Shields and Santana have ERAs below 3.00, and Guthrie's is less than 3.75. Combined with a stellar bullpen anchored by closer Greg Holland, the Royals have the best team ERA in the American League.
That said, ERA is a reflection of more than just pitching. Defense-independent pitching statistics (DIPS) theory tells us that pitchers have very little to do with the chances of an out being recorded once a ball is put in play, an assertion that is supported by the ball-in-play results of most pitchers over large samples. The consistent exceptions -- the pitchers who outperform the league average on balls in play over long stretches -- frequently play in front of exceptional defenses, and that applies to this year's Royals club, as well.