"Two days after manager John Russell said his coaching staff would have to decide whether to keep struggling pitcher Zach Duke in the rotation, Russell said Thursday that the left-hander will start Sunday against the Diamondbacks. "The kid's worked hard," Russell said. "We'd like to give him the opportunity to straighten things out." Russell said Duke has been working on his tempo and arm speed, hoping to make his delivery less choppy and more aggressive. Russell and pitching coach Ray Searage said Duke's side sessions between starts have been excellent, but they haven't been carried over into games. "The biggest thing has been not trusting himself, trying to make his stuff better rather than using the stuff we had in the sides," Searage said. "He's trying to make the slider sharp that much more or the fastball sink that much more or the changeup be that much more of a deception pitch, and he got out of himself. We're trying to help him find his identity, to be Zach again.""