With only a week left until the July 31 MLB trade deadline, two All-Star aces have emerged as the biggest prizes to be had: Dan Haren and Roy Oswalt.

But which pitcher is better?

Is it the the hard-throwing Astro, or the deceptive Diamondback?

Most casual fans might instantly say Oswalt due to the recent struggles of Haren in 2010; however, just last season, the Astros right-hander finished the year with an ERA well above 4.00.

Here is the breakdown.

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