Moore left a 4-2 loss to the Kansas City Royals on Monday night in the fifth inning with a sore elbow. He grimaced after throwing a changeup to Norichika Aoki, which prompted a mound visit from manager Joe Maddon and athletic trainer Ron Porterfield.
"It has to be checked," Maddon said. "There will be tests tomorrow. We don't know what's going on yet. We'll get an update later. He tried to talk me out of taking him out but I said I didn't think it's a good idea. I went out there and I wanted to give him the benefit of the doubt. I like to communicate with our guys. He just felt something on a pitch. We knew we can't take any chances on anything."
The Rays told ESPN's Jayson Stark on Tuesday that Moore will be placed on the disabled list and left-hander Jeff Beliveau is being recalled.
Moore said he would have a MRI on Tuesday. X-rays taken Monday night showed no damage.
"Maybe it's a hyperextension, it's kind of like a bruise," said Moore, who left after throwing 78 pitches. "It's hard to find that uncomfortable feeling."
Moore won 17 games and was an All-Star selection last season, but he went on the disabled list last July 31 with a sore elbow and did not return until Sept. 3. He said in spring training the injury was in "back of his mind."
"Any injury is like that," Moore said. "I hadn't felt it but I was being careful in spring training and we weren't facing live hitters yet. It continued to be in the back of my mind until we started facing live hitters. That's when I completely forgot about it until right now."
He said he initially felt something in the elbow when facing Alcides Escobar, the batter before Aoki.
"It really came out of nowhere," Moore said. "There was no particular pain. I felt it when I was pitching to Escobar, on a changeup, and then I threw two more changeups to Aoki and I felt it. I actually threw a curveball (to Aoki) to see if I would feel it then, too, but I didn't. It may have something to do with changeups in that situation."
Moore said he considered calling Maddon to the mound in Escobar's at-bat and then tried to talk him into staying in the game with a 2-2 count on Aoki. Maddon did not even allow Moore to throw a warm up pitch before bringing in Cesar Ramos.
"I thought, 'give me a second to collect myself,' " Moore said. "I felt good in the moment. I asked Joe to let me throw a couple of fastballs, but he didn't."
Moore said he hopes he can avoid a trip to the disabled list.
"I haven't thought about that," Moore said. "All I can think about is 12 hours from now, tomorrow and the MRI. I can't really speculate. If I had to guess, structurally things are fine."
Information from The Associated Press was used in this report.