Hamilton has been recovering from an intestinal virus and hasn't started since Thursday. He entered Monday's 2-1 victory over the Padres in left field in the ninth inning.
Hamilton said he's around 80-85 percent healthy.
"I feel good, excited to get back in," he said. "I made a little appearance last night. That was fun. I tested it out yesterday. Everything went good."
Hamilton would have pinch hit for the pitcher in the eighth inning Monday if Leonys Martin had gotten a runner on base, Rangers manager Ron Washington said, but Martin recorded the last out of the inning. Hamilton was swinging the bat in the cage throughout the game.
"I'm feeling better. My strength is coming back," said Hamilton, who lost about 10 pounds while dealing with the illness that put him the hospital.
His 3-year-old daughter is still sick with the same virus.
Hamilton said he's looking forward to playing in Petco's expansive outfield.
"I like big outfields," Hamilton said. "When balls are hit, you get a chance to run them down and make a good play on them. I just have fun with it."
Hamilton will face one of the pitchers involved in the trade that brought him to the Rangers. The Cincinnati Reds traded Hamilton in 2007 to Texas for Danny Herrera and Edinson Volquez, who starts Tuesday for the Padres.