The neurologist treating Stuart High School football player John Avila said yesterday that although his patient was still in critical condition in the intensive care unit of Alexandria Hospital, "his chances of living have improved right now, but at what level of life, we will not know for some time."

Dr. Juan Jammes of Alexandria said Avila, who suffered a life-threatening brain injury in a football game Friday night, had several minor setbacks yesterday. He had a slight fever that can become a serious problem in comatose patients because of the possibility of infection, and seizures in his right arm and the right side of his face, indicating damage to the left side of the brain.

The seizures and the fever are being controlled by medication. Jammes also said he was encouraged because Avila, a 17-year-old senior, had longer periods of breathing on his own, though he is still on a life-support system.

Another electroencephalogram (EEG) test was administered yesterday, and the doctor said the brain wave activity was about the same as it was in a similar test performed Tuesday.

"We see some progress," Jammes said. "Today, there has been a tiny dropback because of the fever and the seizures. But we are also hopeful that he can come out of the coma. Again, it is still too soon to know very much.

"Could he recover as far as life is concerned? The answer is yes. Completely? No. I expect that he would have significant defects. To what extent, who knows. He will function at a lower level, at best. But the extent of the recovery, I cannot say.

"Could he recover his speech? Will he recover the function on the right side of the body? Will he continue to have seizures? Those are issues that cannot be determined at this time."

Avila had 4 1/2 hours of surgery early Saturday morning to relieve pressure on his brain caused by bleeding, and he has been in a coma since. He apparently suffered the injury during the game, walking off the field on his own in the third quarter, then collapsing on the sidelines several minutes later.

Jammes indicated that, in the next few days, Avila may be able to breathe on his own without the respirator. "That's a good sign," he said.

Jammes said that Avila's parents "are being realistic. These are people who know the limitations of medicine. But at the moment, they do not have any decisions to make. The law says a patient can be taken off life support if he is brain dead, and this patient is not brain dead. A patient can be taken off if the situation is irreversible. In this case, it is not irreversible.

"Because he is so young and so strong, we have to wait much longer to see how he will respond. That is all we can do."

Manny Fierro, a spokesman for the Avila family, said yesterday, "As far as the family is concerned, they are guardedly optimistic. When they found signs of life with the brains waves Tuesday, that rejuvenated them. The prayer service Monday night also was a big help. It showed that so many people care about their son.

"But they are still guarded because the things go up and down. Right now their spirits are up. So they are taking it one day at a time." Washington Post staff writer Dave Sell contributed to this report.