Moore made his sixth start on Saturday, allowing six runs on nine hits and a walk with two strikeouts. Though Moore worked just three innings, he threw 70 pitches (46 strikes). He is 1-3 with an 8.78 ERA for the season.
"I am discouraged and disappointed the way the results have [gone]," Moore said.
The move will leave the Rays with a rotation consisting of Chris Archer, Jake Odorizzi, Nathan Karns and Erasmo Ramirez. The Rays have some off-days that will allow the team to go without a fifth starter for a while.
Dr. James Andrews performed the surgery on Moore's left elbow on April 22, 2014, in Pensacola, Fla. After 451 days in between Major League starts, Moore started against the Indians on July 2 and pitched 4 2/3 innings. Since then he has completed five innings twice in six starts.
Given Moore's performance, the Rays were left in a precarious position when considering how to proceed. He is a big part of the team's future. However, the Rays remain in contention so they could not afford to continue giving the ball to Moore every fifth day and expect things to change.
When asked after the game if he thought the Rays might send him to work on things in the Minors, Moore noted: "I mean that sounds like, probably, a better question for management."
Rays manager Kevin Cash indicated after the game that the situation was one the Rays needed to "talk through as a group" to decide on their plans.
"Matt is in a unique situation," Cash said. "He is coming off the injury. So we need to factor that in. But obviously, we need Matt Moore to get back to the way he's capable of pitching.
"There have been signs of progress throughout these starts and then there's been some others that have been rougher."
Moore seemed frustrated when he told reporters, "It's not fun right now." But he sounded determined when he added, "But I still believe in myself."
"I still feel like when I was out there competing today, I wasn't being timid," Moore said. "That was what I had to offer today. It's tough only going three innings and handing over that many innings to the bullpen. It doesn't feel good. But I think it's days like this that make the good days the great days."