Bourn Expanding Zone as a Brave

When Atlanta acquired Michael Bourn from the Astros at the trade deadline, they thought the leadoff hitter would work deep counts and cause mayhem once he got on base as the Braves coasted to a Wild Card berth. Instead, Bourn has a .313 OBP with his new club, which is now tied with St. Louis in the Wild Card standings.

Bourn's OBP has taken a tumble and his walk rate has declined (from eight percent as an Astro to 5.8 percent as a Brave) because he's swinging at more pitches thrown both inside and outside of the strike zone:

Bourn's 2011 swing rates

As an Astro: 60.6% in-zone swing%, 25.6 chase%, 41.6 swing% overall

As a Brave: 65.2 in-zone swing%, 29.1 chase%, 47 swing% overall

In particular, Bourn is swinging at more in-zone pitches thrown inside, and more out-of-zone pitches located outside . Check out his swing rate by pitch location with Houston, and then with Atlanta:

Bourn's swing rate by pitch location, Houston 2011

Bourn's swing rate by pitch location, Atlanta 2011

Bourn chased 26 percent of pitches thrown outside as an Astro, right around the 25-26 percent league average. But that outside chase rate has climbed to 32.1 percent as a Brave. That's a big change, considering about 59 percent of the pitches that Bourn has seen this year have been thrown outside, and no NL hitter save for Prince Fielder has gotten more outside pitches thrown off the plate. In order to boost his OBP -- and the Braves' tenuous playoff hopes -- Bourn has to show some restraint on the outer third.