For now, it's just Haren, who will face the San Diego Padres in his first opening day start since he came to the Diamondbacks in 2008.
With Webb making a slower-than-expected comeback from shoulder surgery, Haren is the unquestioned ace of the pitching staff. He will be making his second career opening day start. His first was with Oakland in 2007.
The Padres will counter with Jon Garland, who had a brief, mostly unsuccessful stint with Arizona last season. Garland disputes the perception that he hates throwing at Arizona's hitter-friendly Chase Field.