Earlier in the day, the Rangers said Feliz would remain as their closer, helping a relief corps that has struggled this spring. The AL Rookie of the Year had been in the mix for a starting spot after posting 40 saves last season.
Feliz gave up a leadoff double in the eighth before getting out of the jam.
"Right now, for our organization, he's better in the bullpen," Texas manager Ron Washington said. "We haven't closed the door on him being a starter. It's just not now. We wanted to make sure that we continue to be strong in every area. With Feliz being at the closing end, we're certainly strong."
San Diego center fielder Cameron Maybin left the game with tightness in his right quadriceps. He grounded out in the first inning and made one catch in the bottom half before giving way to Jesus Guzman in the second.
Maybin was acquired from Florida in the offseason after playing only 15 games for the Marlins last season. He is hitting .341 and has scored 10 runs this spring.
Padres starter Aaron Harang went five innings, allowing four runs -- three earned -- and six hits.
"A couple of times tonight, the way the ball was flying out, I felt like I was back in Cincinnati," said Harang, who signed with San Diego in the offseason after seven-plus seasons with the Reds.
Texas RHP Dave Bush started in place of Feliz and allowed four runs, three earned, and four hits. RHP Brett Tomko followed and threw two one-hit innings. The two veterans are competing against each other for the Rangers' long-relief role. Washington said Tomko likely could throw five innings if needed but that he's considered in the organization strictly as a reliever.