"Joe Mauer's eyes looked tired, his voice was strained, and he had to pause several times to cough, but the Twins catcher offered several reassurances Monday that he is dealing with pneumonia and nothing else.

"When they discovered pneumonia down at the Mayo Clinic [on Sept. 15], that's what they do, they check over everything," Mauer said. "That's what they came up with, and that's what they're treating."

It was the first time Mauer was available to the media since he last played on Sept. 14. Doctors told him to stay home during the Twins' last homestand, but he got clearance to return to Target Field on Monday, as the Twins opened their final three-game series against the Royals.

"If you don't treat something like this, it can linger, and it's definitely not what we want to do," Mauer said. "I have to come back strong and healthy [next season], just like any other year."

Mauer was asked repeatedly if he's concerned he's dealing with something more serious. At age 28, in the first year of an eight-year, $184 million contract, he was limited to 82 games and batted .287 with three homers and 30 RBI, while dealing with multiple injuries and ailments."