Diamondbacks pitcher Trevor Cahill was designated for assignment a few days ago and has cleared waivers. And now, he's been optioned all the way down to the High-A Visalia Rawhide, the club announced Thursday. Cahill, 26, is 1-6 with a 5.66 ERA (66 ERA+) and 1.74 WHIP on the season. He began the season in the rotation, but after an 0-4 start with a 9.17 ERA, was demoted to the bullpen. This season has been quite the downward spiral for Cahill. Remember, he was an All-Star and finished ninth in AL Cy Young voting in 2010 when he went 18-8 with a 2.97 ERA at age 22.