"Retirement is not a consideration," Aikman said Wednesday. "It's not something I'm thinking about or even weighing as an option right now. I feel that in time I'll be fine and be able to resume playing. I anticipate that will happen very soon."

Aikman, who has never missed a game because of a concussion, said it would be wrong for him to even speculate how long he'll be out. An MRI taken Tuesday came out fine and more tests are planned for later this week.

"I'm hopeful that it will just be one game," he said. "But it's not something that I or our doctors want to rush."

Time is working against the Cowboys. Dallas (4-4) plays three times in the next two weeks: Green Bay at home Sunday, the Cardinals in Arizona the following Sunday and at home against Miami four days later on Thanksgiving.

The Cowboys, who've lost four of their last five, also go into that stretch without Emmitt Smith or Michael Irvin. Dallas hasn't been without all three since Smith was drafted in 1990.

Smith had a plate and screws inserted into his right hand Tuesday to repair a broken bone. He's still expected to be out 2-5 weeks. There's no telling when or if Irvin will return from a spinal cord injury.

Aikman was relaxed as he stood in front of his locker in his typical midweek pose. Wearing a Cowboys cap turned backward, gray workout shorts and a gray T-shirt, he stood with arms crossed and leg bent.

His tone was as confident as the week before when he discussed the impact of a helmet-to-helmet hit from Indianapolis' Jeff Burris. That blow wasn't ruled a concussion, but Aikman said Wednesday doctors now say it was.

That diagnosis became obvious Monday night when a less-violent hit by Minnesota's Jerry Ball left Aikman feeling even worse than the collision with Burris.

"The headaches are probably about the same," said Aikman, who said he doesn't remember being sacked by Ball. "Some of the dizziness and uneasiness is something I didn't experience last week."

Aikman missed only one series against the Colts, then played the final two possessions. He had headaches for at least five days, but never considered sitting out against the Vikings and was cleared by doctors to play.

"I think the decision to play against Minnesota was an informed decision and I think it was the right decision," Aikman said. "If I was to have another one and two days prior to a game I felt fine and ready to play, I would do that."

Aikman has had seven concussions in the NFL and nine overall. Each one makes him more vulnerable for the next and they're likely to last longer.

That's what ended Roger Staubach's career after 11 seasons in Dallas -- this is Aikman's 11th season in Dallas -- and it's the reason San Francisco's Steve Young is being advised to retire.

"I think that's why there is as much concern as there is," Aikman said. "That's why I think the approach is to make sure I'm 100 percent ready and not experiencing any of the symptoms."

Aikman and Young have the same agent, Leigh Steinberg. Steinberg has extensively studied concussion and organized three seminars on the subject, including one Aikman attended three years ago.

The sobering reality for Steinberg is that time is the only way to truly determine the damage done, and by then it's usually too late.

"Ultimately, we don't know which head injury will be the one that triggers future damage such as Alzheimer's or Parkinson's," Steinberg said.

Simply hearing those diseases mentioned is enough to prompt Aikman's loved ones to tell him to retire while healthy enough to enjoy his millions.

"I think with family and friends, there is always concern," Aikman said. "Everybody's got moms and they don't ever like to see their boys out there getting hit. It's no different in my situation.

"But they understand it, they've grown up with it. They know how important it is to me and the risks we take. There's obviously concern, but they want me to do what I feel is best for me."