You look at Reggie Williams, thin as the ace of diamonds, and wonder how anybody with that build can be so effective at virtually every position.

You could search all day trying to find bulging muscles on his 6-foot-7, 185-pound body. And the fact that Williams has the sweetest little baby face -- despite his recent effort at growing a beard -- makes it appear as if he'd get mangled if he even thought about going close to the basket.

But if a coach could send out a team with four Reggie Williams, one each at point guard, off-guard, small forward and even power forward, he probably would land that team in the Final Four. In the last few games, he has played in the low post, too, meaning that Williams actually has been been exposed to all five positions offensively. He is a primary reason Georgetown is 20-6 in The Year After Patrick.

"People keep talking about Walter Berry going hardship; I wish Reggie a junior would go hardship because I'm tired of having to play against him," Syracuse Coach Jim Boeheim said recently. "He's the best offensive rebounder in the league, even though he's more a guard. He just knifes in there and gets inside. He's underrated, even now. It was hard for him to get any kind of buildup with Patrick there. But he's clearly one of the best five players in the country this year."

Williams' numbers are way above average, if not spectacular. Going into tonight's 8 p.m. game against Boston College at Capital Centre, he is averaging 19 points on 52 percent shooting in Big East games. He also has 9.0 rebounds per game. Last year, Ewing averaged 9.2 rebounds.

"He might do as much offensively as anybody who's ever been here," Coach John Thompson said. "He can post-up inside, shoot it from the corner. I'd feel very comfortable with him bringing the ball upcourt several times in a row as the point guard. People talk about doing all those things. Reggie can do them very well. He's everything you'd want in somebody that size."

Williams' versatility -- maybe only John Williams of Louisiana State and Danny Manning of Kansas play as many positions as well -- developed as a direct result of playground encounters; one with a player with an extremely long reach, and another with his best friend, 5-foot-3 Tyrone (Mugsy) Bogues.

"Believe it or not," Bogues said, "Reggie and I used to be wrestlers. We were in different weight classes, but we gave it up at 12."

On the playgrounds around the Lafayette housing project in East Baltimore where they grew up, no dribble was safe from Bogues, now the point guard at Wake Forest. Williams always could shoot, but not without the ball. So Williams, with Bogues' help, learned to handle the ball, as well.

"As soon as he'd grab the rebound, I'd start screaming, 'Big fella, big fella,' " Bogues recalled. "He knew if he ran the court and filled the lane, I'd get it back to him and nobody else. Even then, 75 percent of the time nobody could stop him, even though we all knew he would get the ball."

The other 25 percent of the time a guy named Jeffrey Johnson and his long arms were making Williams' life miserable.

"I was smaller back then," Williams said. "I always had to pump- fake to get my shot off. When I was 11, there was this guy, Jeffrey Johnson -- I think he's in the service now. He would always block my shot. I would get mad at him. 'You keep on blocking my shot.' And he'd keep laughing at me and keep blocking my shot. Every day he'd block and laugh.

"That's when I said, 'I've got to do something. I've got to learn to go to the boards, or something.' The next year, it was a whole different thing." Almost never, is how often Williams gets his shot blocked now.

An incredible variety of releases makes Williams' inside scoring as effective as his jumper. He's a sneaky shooter. Thompson says Williams learned how to be "slick enough" to get off his shot. Williams' favorite shot is a sky hook. He threw one over Berry earlier this season. His jab-step jumper is especially effective because the moment Williams acts as if he's going to drive, the defender has to back off.

It's just part of the reason he can excel at so many positions. Even though Williams played mostly power forward at Dunbar High, Coach Bob Wade installed a play (when Williams was a junior) for him to handle the ball in the delay game. Guarded by a man his own size, Williams would sucker some poor defender into a layup time after time. "You could see he was such a natural talent, there was no sense in chaining him down," Wade said.

It's not unusual, in fact, for Williams to play four positions on one or two possessions during a game. If Michael Jackson is getting a rest on the bench, Williams might assume the point duties until he gets the ball to half court. He might then play on the top, looking for the outside jumper like a guard, rotate to the corner as small forward, and go right inside like a post player, seeking the offensive rebound.

Despite having a tender ankle for much of the season, Williams had 10 rebounds or more eight times this season.

After Williams sliced through three Syracuse players who were taller and considerably heavier for an offensive rebound Sunday, 6-10 Orangeman center Rony Seikaly said, "How does that guy get rebounds like he does?"

Williams is even surprising Wade. "When he grew to 6-7 as a senior, we expected him to get 12 or 13 rebounds a game. But that was high school. On the college level, it has really surprised me that he can, game in and game out, go inside and pull down nine and 10 rebounds against those power players.

"He's always had a great eye for the ball. He anticipates really well. And he just maneuvers his body into the open areas."

Williams, body by Gervin, really is small enough to shimmy into a hole where a 220-pounder can't fit. "Quickness," Williams said. "The bigger guys, I can maneuver past them. Plus, I can jump. I can't go in there banging for 40 minutes a game. I can do enough to get away with a little of it."

Even though Williams was able to play so many positions, he didn't really expect to do so as a freshman at Georgetown. It was difficult enough for a freshman to adjust to the turmoil Georgetown was going through en route to winning the national title in 1983-84.

"Back when I was in high school, I didn't pay that much attention to Georgetown, and this 'Hoya Paranoia' stuff wasn't around yet," Williams said. "My first year, it all started. It was hard to get used to. There was so much pressure all the time. Win, and you're wrong; lose, and everybody in the whole world is happy . . . . We were out west for three weeks. Other than going to summer camp, I had never been away from home a real long time. It rained every day we were in Seattle. It was just a whole new world for me."

Still, Williams had a standout freshman season, highlighted by a 19-point, seven-rebound performance in Georgetown's 1984 NCAA championship game victory over Houston. "It's very unusual to see anybody, other than the really great ones, come in at that age and perform that way in the big game," Thompson said.

There was an indication then that Williams was made for big games. In the 1984 Big East tournament against St. John's, he had 17 points and five assists. A little earlier, at Syracuse, he shot 10 for 13 from the field and grabbed seven rebounds. This season, he had 16 points and 16 rebounds in a four-point victory over Connecticut, and 22 points and 14 rebounds in a four-point victory over Villanova.

Thompson says Williams has to work on his defense. Williams agrees. Bogues, in his critique sessions with Williams over the phone after games, might say the same thing now and then. Wade says he's rarely seen two youngsters talk so much about the nuances of basketball.

Williams probably won't make first-team all-America this year, despite all the coaches and players who say he is one of the best five players in the country.

"I like the recognition," he said. "But I decided in high school I wanted to learn the whole game, how it all works. I could have gone to a place and averaged 25 points. But I wanted to be known as a team player."

When you consider the fact that he plays four positions, how could he be known as anything else?