(Reuters) - The Cincinnati Reds put ace pitcher Johnny Cueto on the 15-day disabled list on Monday as they continue to battle injuries in the opening month of the season.
Cueto was hurt while pitching against Pittsburgh on Saturday and was diagnosed with a strained muscle in his back.
"This is unbelievable," the Dominican told reporters.
"I felt so good. I've been pitching so relaxed that I didn't believe this could happen now the way I was feeling. One pitch I threw, I felt this and that was it."
The 27-year-old Cueto joins left fielder Ryan Ludwick (torn labrum in right shoulder) and lefty reliever Sean Marshall (shoulder tendinitis) on Cincinnati's early season DL list.
Cueto has gone 1-0 with a 2.60 ERA this season. He helped guide the Reds to a division title in 2012 when he finished 19-9 with a 2.78 ERA.
The club promoted right-hander Justin Freeman from Class AAA Louisville to assume Cueto's roster spot.
(Writing by Jahmal Corner in Los Angeles; Editing by John O'Brien)