Affeldt's time in the bullpen did not last long. On May 3, he replaced Bryan Rekar in the Royals' starting rotation. In his first start, he pitched four innings, gave up one run, and earned a no–decision in a 4–3 loss to the Baltimore Orioles. Affeldt's time as a starter garnered so-so results, as he was 0–4 with a 5.45 ERA in seven starts. In his last start, on June 8, Affeldt picked up the loss as the Royals fell 11–3 to the St. Louis Cardinals. After getting pulled in the fourth inning due to an injury, Affeldt was placed on the disabled list with fingernail and blister problems.