Feliz, who turns 23 on May 2, has pain in the rotator cuff, something that has bothered him going back to Spring Training. He first told the club of the shoulder pain after pitching in cold weather in New York during a weekend series April 15-17. Feliz pitched again Wednesday against the Angels and had two walks.
"If he was 33 instead of 23 we may treat it a little differently," Daniels said, "but given his age and what he means to the club, we're going to play this one on the safe side, relatively conservatively. We very easily could have just given him a couple of days off and see how it goes. But we didn't want to take any chances here."
Because Feliz last pitched on Wednesday against the Angels, the move is retroactive to Thursday and he is eligible to be activated on May 6.
Manager Ron Washington said he would handle filling the closer job by committee to begin with, leaning toward veteran left-handers Arthur Rhodes and Darren Oliver. Washington also said that he might ask any of the relievers to close out games, depending on matchups.
"Whoever is down there, we'll do what he have to do to close it out," Washington said. "You're always going to go to one of the veterans first. But if those veterans are not available, then it will be someone else. If one of them steps up, then they'll step up. We've got no bona fide closer right now. It's that simple."
The Rangers hope they won't have to go without Feliz for long. He has been placed on medication and in the last couple of days has added an additional stretching program. Daniels said he can't make a 100-percent guarantee, but he expects Feliz to be ready to pitch when his DL time ends.
Feliz said he doesn't feel good about going on the DL, but he's trying to take it in stride.
"I know that it is good for me," Feliz said. "And it is the best way for me to take a couple of weeks because it's a long season. I feel a little tight behind my shoulder, a little bit tighter, like when I release my arm as I used to."
Rhodes and Oliver have combined for 34 saves in 1,456 appearances in the Major Leagues. Rhodes last had a save in 2008 with Florida. Oliver had a save last season for the Rangers, and before that his last one was in 1994. Right-hander Darren O'Day, who has struggled early in the season, also has two career saves.
Rhodes and Oliver both said they will not change their approach. The 40-something relievers have already seen it all.
"It's not going to change our role, because the eighth inning and the ninth inning are about the same," Rhodes said. "Nefty's out, so we've just got to step up our role and do what we've been doing."
"You play this game long enough, things like this are going to happen," Oliver said. "It's unfortunate that he went down like he did, Nefty, but we know he'll be back. Better now than later."
The club called up right-hander Cody Eppley from Triple-A Round Rock to replace Feliz on the active roster. To make room for Eppley on the 40-man roster, Texas placed right-hander Eric Hurley on the 60-day disabled with post-concussion symptoms.
Todd Wills is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.