Stephenson, 23, didn't fully see this move coming. He was cut from the Spring Training roster late last month. And then he struggled in a final start for the big league club when he returned from Minor League camp.
"They told me to be prepared in case anything crazy happened," Stephenson said. "I was definitely surprised and I'm extremely excited to be here."
Cincinnati broke camp with a vacancy for the third start of the regular season -- Thursday vs. the Phillies. It was made possible with five pitchers needing to go on the DL. Stephenson had an inconsistent spring while posting a 9.58 ERA in four starts, but he got the nod over candidate Tim Melville in large part because he was on the 40-man roster and Melville was not.
Despite having some command issues, manager Bryan Price still felt comfortable giving the ball to Stephenson -- the club's No. 2 prospect per MLBPipeline.com. The righty was 8-11 with a 3.83 ERA in 25 starts last season for Double-A Pensacola and Triple-A Louisville.
"He's touched every level, which helps," Price said. "He was at Triple-A last year. He was in his third big league camp, even though he didn't pitch last year in camp [because of injury]. That's an easier decision when you know you have a guy that's pitched at every level of professional baseball. He's 23, a little more seasoned. He had a full Major League camp and opportunities to pitch at the big league level. To me, it just seems to make sense."
Stephenson received the news of his promotion Sunday and flew into Louisville from Arizona before driving to Cincinnati on Monday. He threw a bullpen session and felt ready. Admitting he was nervous in his last spring start knowing the opportunity before him, he wasn't concerned about butterflies in an even bigger environment.
"The only thing I want to do is go out there and have fun," Stephenson said. "I think it's a good opportunity to go out there and get my feet wet and a little bit experience. That way when I come back for a more permanent time, it's not new to me. It takes the weight off my shoulders a little bit."
Price noted that a strong first start could earn Stephenson more time in the Majors, so this should not be the last the Reds see of the prospect in 2016.
"It may not be the next time through the rotation, but it might be the first time we need somebody else to start," Price said. "We get excited by our players that haven't been in the big leagues when they come and they perform."
Mark Sheldon is a reporter for MLB.com. Read his blog, Mark My Word, follow him on Twitter @m_sheldon and Facebook and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.