PHILADELPHIA - It's a broken bone that could mean a broken season for the Philadelphia Eagles.

Quarterback Donovan McNabb suffered a fractured right fibula, one of two bones in the lower leg, near the ankle, early in yesterday's 38-14 victory over the Arizona Cardinals at Veterans Stadium. He finished the game, but he might be finished for the season.

"It's normally a six- to eight-week injury," coach Andy Reid said.

There are six weeks left in the Eagles' regular season.

After taking last night to discuss the situation with his family, McNabb, who became the NFL's highest-paid player when he signed a $113 million contract in September, will be reevaluated by the Eagles' medical staff. He likely will get opinions from another doctor or two. He might have to decide between having surgery and allowing the bone to heal on its own.

Reid, McNabb and the medical staff thought that the injury was a sprain until a post-game X-ray revealed the fracture. The break was "clean," according to one team source, and didn't appear to have been made worse by McNabb's continuing to play.

"We obviously didn't know this [that it was broken]," Reid said. "We thought he sprained his ankle, and I wanted to make sure he could push off it, and he was able to do that. He wasn't going to come out."

Leaning on crutches during his post-game news conference, McNabb said he had thought the ankle was sprained and that he wanted to stay in the game.

"I actually didn't want anybody to touch it," McNabb said. "When the game was going on, I just tried to do whatever it took to win the game."

McNabb was injured on the game's third play from scrimmage. He dropped back to pass and then stepped up as the Cardinals put pressure on him.

As linebacker LeVar Fisher and safety Adrian Wilson converged on McNabb, his right leg folded awkwardly beneath him. He fumbled the ball, turning it over to Arizona, then remained on the field for a few long moments.

After getting the ankle taped, he got up and walked around along the sideline. As the Cardinals were driving to a touchdown, he began to jog.

When the Eagles' offense returned to the field, McNabb was out there. Not only did he play, he played one of the best games of his career. He wound up completing 20 of 25 passes for 255 yards, and his four touchdown passes tied a career high.

As the game went on, McNabb limped more noticeably. He later said that the ankle had hurt throughout the game. "I just blocked it out," he said.

The Eagles built a 28-14 lead at halftime. After throwing his final touchdown pass with just over a minute left in the first half, McNabb walked up the ramp to the locker room. No X-rays were taken at that time.

McNabb played until midway through the fourth quarter, when the Eagles had a 38-14 lead. Backup Koy Detmer finished the game.

McNabb finally went to the locker room. The Eagles' medical staff, still assuming the ankle was merely sprained, took an X-ray as a precaution. The X-ray showed the fracture.

McNabb appeared stunned by the news and continued talking as if there was a chance that he would play next Monday night in San Francisco. He won't.

"It definitely is [a shock]," McNabb said of his injury. "This is the first [serious] injury I've ever had. I didn't get hurt so I would [miss a game] in college. I never really got hurt in high school. So to get hurt now is something to deal with."