"I felt like I threw the ball pretty well, but it's one of those things; that's just how it works," Niemann said. "That's kind of how it works. It's totally out of my control."
Niemann was told of the decision by Rays manager Joe Maddon prior to Saturday's game against the Pirates. His departure leaves J.P. Howell, Edwin Jackson, Andy Sonnanstine, and Jason Hammel as the remaining contenders to fill out the rotation. Maddon said that he would announce his rotation later.
Niemann, Sonnanstine and Howell all have options left, while Jackson and Hammel are out of options, meaning they would have to clear waivers before the Rays could assign them to the Minor Leagues.
Niemann, who was the Rays' top pick in the 2004 June Draft, has battled injuries throughout his career, but was healthy in 2007 and pitched well this spring, posting a 2-0 record with a 1.50 ERA in four games.
The 6-foot-9, 260-pound right-hander said that Maddon told him to continue to work on his consistency and on keeping the ball down.
"All stuff we've been talking about," Niemann said. "Just fine-tune."
Despite his disappointment at getting sent down, Niemann said that he felt better about his pitching than he has at any point in his professional career.
"I'm more in control, the way it's feeling, it's more natural," Niemann said. "I'm not searching for things. That's the biggest thing. I have a plan of attack and keys I can go back to and make adjustments. Whereas last year I was just throwing it. Hoping for the best."
Bill Chastain is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.