Kevin Walker found out early about the frailty of life in the NFL. Six games into his pro career, the former Maryland linebacker was contemplating the possible end of it.
His left knee had been ravaged by a clip on a kickoff, and Walker listened with incredulity as the Cincinnati Bengals' team doctor told him along the bench that he would need total reconstructive surgery.
As he was carried into the locker room, Walker says, "I didn't know if I'd ever play again. It was just the worst feeling. It's still vivid. I remember it like it was yesterday."
It was, in fact, October 1988. Walker's rookie season ended with him chasing down a ballcarrier, getting cut down by an illegal block. He spent the rest of the year on injured reserve, then watched the Bengals lose the Super Bowl from the sidelines.
Of such tenuous beginnings are NFL careers built.
Two years later, Walker, 24, is a starting inside linebacker on a team that many believe has a good chance to get back to the Super Bowl. After surgery, he spent nine months in rehabilitation and 16 regular-season games trying to break into the starting lineup. "I didn't miss a practice or a game [last year]," Walker said yesterday, proud of the point.
The realization that football could be fleeting was what drove Walker back to College Park last January. Three classes short of graduating, he went back to get his degree in consumer economics. He graduated in May.
"The injury opened my eyes to the reality of the sport," he said. "Your career is one play from being over. It's just a reality I came to terms with. Once I was hurt, I knew I was going back to school."
The door of opportunity swung open this summer when the Bengals moved Walker from outside linebacker -- he had been groomed as Reggie Williams' successor -- to an inside spot in their 3-4 defense. It swung open wider yet when veteran Joe Kelly was a holdout most of camp. And when Kelly was traded at the end of preseason to the New York Jets for receiver Reggie Rembert, Walker had the starting job.
"With Joe not in camp, it gave me the opportunity to get that many more snaps," he said. "It enabled me to progress. I think I still would have been playing [if Kelly hadn't been traded], but no question I wouldn't have been playing as much."
Walker, a native of West Milford, N.J., had been an inside linebacker at Maryland, and the switch inside at Cincinnati was met with a sigh of relief. In two games he has had 19 tackles.
"It's a more aggressive type position," he said. "You attack what you see. Playing outside, you have to be a good pass rusher, No. 1. And you have to know when to be physical, when to finesse. Playing the flank part of the defense is very important because when the ball gets outside, it's a big play."
Playing inside affords less opportunity for sacks, but Sunday, in a 21-16 victory over San Diego, Walker delivered his first of the season. Late in the fourth quarter, with the Bengals protecting their lead, he broke through to dump Billy Joe Tolliver.
In Week 1 against the Jets, Walker contributed to a goal-line stand when he was in on a first-down tackle with the Jets perched on the Cincinnati 1. The Bengals held the Jets to a field goal and then rallied for a 25-20 win.
Of such beginnings are Super Bowl seasons made.
"Go back to our Super Bowl season  and you'll see we had two goal-line stands against the Cardinals in the opener," he said. "That set the tone for the season."
Walker obviously hopes the tone has been set again in 1990.