It was an ordeal for Paul Konerko just to walk up a flight of stairs on Aug. 10.

"I felt like I was going to throw up after that flight of stairs," Konerko said Friday as he described the helpless feeling he experienced for three days after he suffered a concussion Aug. 7. "That's when I knew it was real. It was something that you can't mess around with."

Konerko said he gained a full understanding of why a minimum of seven days are required for players placed on the DL for concussion symptoms and gained new respect for players who return from that ailment.

"It's a very peculiar feeling. It's very depressing," said Konerko, who said it hurt for several days just to shift his eyes. "You feel not yourself. You almost feel, you don't care about anything. You're so depressed and unmotivated to do anything. You have no energy, no anything.

"You just feel like a different human being. You just feel like out of the world. It's just a weird feeling."

Konerko passed an impact test on a computer that compares to a baseline test that he performed in the past, as well as a written test the day after he was elbowed by the Royals' Jarrod Dyson and passed a series of cardio and baseball drills earlier this week.