The Pirates optioned Curtis to Triple-A Indianapolis on Sunday, Danny Demilio of PittsburghBaseballNow.com reports.
The right-hander received his first promotion to the big leagues Saturday and made his MLB debut in the second game of a doubleheader in Cleveland with five scoreless innings of bulk relief. Curtis should have a better chance of returning to the majors later this summer now that he's on the 40-man roster, though his 4.96 ERA in 18 appearances between the Double-A and Triple-A levels could be a limiting factor, even after his strong performance Saturday.