Feliz posted 40 saves last year, then came to camp trying to win a spot in the Texas rotation. Earlier this week, he said he'd prefer to stay in his closer role.
"Your heart's got to be in what you're going to do," Rangers manager Ron Washington said. "If your heart isn't in it, we'll have to make that decision down the line."
Feliz took over in the sixth inning and allowed one hit and walked two. He threw 53 pitches, 30 for strikes, and showed off a sharp slider to add to his curveball and 100-plus MPH fastball.
Feliz was a lifelong starter until his move to the bullpen as a late-season callup to the bullpen in 2009. No matter what his role, pitching coach Mike Maddux said the extended repertoire can only be of benefit.
"When you always have the almighty equalizer in your back pocket, you can use your other stuff and protect it," Maddux said.
Feliz started to tire in eighth, walking the first two hitters he faced. But he finished in impressive fashion, striking out Josh Horton and Jai Miller to close out his day.
"One of the things he showed last year," Maddux said, "is he may be a youngster but he's a man."
Maddux has asked somewhat rhetorically whether it's better to have such an effective pitcher for 70 innings or 200-plus. At the same time, he conceded Wednesday that "you're only as good as your bullpen."
"It all sounds great right now but come the regular season and we've got a lead after 8½, then let's go win it. He doesn't have to be perfect. You don't have to be perfect as a closer. You just have to be pretty good and you'll have the advantage," he said.
As Feliz and the Rangers mull his ultimate fate, one of his would-be competitors for a spot in the rotation, Derek Holland, posted a stellar outing in his second start.
The left-hander gave up two hits and faced only one hitter over the minimum in his three-inning stint, striking out four.
"I need to show that I belong in that rotation," Holland said. "I don't want anything else. I'm trying to get that starting rotation spot. I need to make a couple of statements and today was one."
Oakland starter Dallas Braden allowed four runs and four hits before recording his first out, though he settled down in the final two innings to finish with five runs -- three earned.
Braden, 11-14 with a 3.50 ERA in 30 starts last year, said his approach will certainly be different once the season begins.
"If it's that way in April, then we have a problem."
David DeJesus and Landon Powell each hit their first home runs of the spring for the Athletics.
NOTES: A's OF Ryan Sweeney made his spring debut and got two hits. ... Michael Young and Yorvit Torrealba each had RBI doubles in the Rangers' fix-run first. ... Rangers 2B Ian Kinsler singled to lead off the game and extend his hitting streak to seven games. ... Rangers RHP Brandon Webb threw 62 pitches in his first live batting practice session of the spring. ... Oakland 1B Daric Barton didn't make the trip with a bruised calf but is expected to play Thursday. ... Oakland RHP Craig Breslow is day-to-day with a strained left hamstring and will not pitch on Thursday as originally scheduled.