Bo Ellis can be excused if he occasionally looks over his shoulder during practices at the Washington Bullets' rookie camp. It is a habit he formed during four years at Marquette while waiting for an inevitable outburst from Al McGuire.

"Hey Bo," McGuire would yell after Ellis messed up a play. "What were you doing before practice? Daydreaming?"

Bullet workouts under Dick Motta so far have been as calm and relaxed as McGuire's were noisy and spirited. And Motta actually teaches step-by-step fundamentals, something McGuire left to his assistants.

The circus at Marguette - the name given to Warrior practices - used to get so bad that Ellis frequently would wander to the sidelines, sit down and dribble the ball through his legs and around his back, no simple feat for a 6-foot-9 forward. It was one way for a player to keep his sanity in McGuire's turbulent world.

"You can't argue with the man's ways," Ellis said yesterday. "He won for 13 or 14 years doing things differently than anyone else.

"It was important to understand the man. Once you knew what he wanted and how he went about getting it, the rest was easy. He would give out the philosophy and his assistants would handle the tactics."

Ellis is a glowing example of McGuire's handiwork. He is fundamentally sound on the court and extremely well-rounded out of uniform. He is a free thinker who is street-wise, while still being confident enough to handle himself in more sophisticated situations.

If his basketball career doesn't work out, Ellis hardly will be reduced to begging for a job. He majored in broadcasting - "I figured my play in the pros would open up opportunities" - while also getting enough work in the art design area to qualify for a job next summer with McGuire's new employer, Medalist Industries.

Ellis designed Marquette's shirt-out-of-pants uniforms. He spent part of his time at Marquette attending an exclusive Catholic women's college so he could take art and design classes.

The sight of a 6-foot-9, bearded basketball player walking the halls of that school must have been shocking at first, but Ellis long ago grew accustomed to special attention.

"Guess it's my body," he said with a smile. "People are always telling me I'm too skinny. You might not believe this but I got up to 203 pounds this summer. But I might be down to 188 now. It fluctuates."

Ellis does look like a human crane in a basketball uniform, with those long arms darting out to knock away shots that seem destined for a safe arrival in the basket. His first collision, however, with Wes Unseld in practice might prove unhealthy, although Ellis insists he's stronger than he looks.

"I'm trying to build up my stamina and strength," he said. "Already, I can tell in these practices that this is a lot rougher world.

"I've always existed by being quicker than the other guy and by being smarter and trying to outthink him and trick him. Mine hasn't been a physical game. I wasn't built for it and I knew it. I never used my hands like they do here."

His wits on the court impressed North Carolina's Dean Smith so much that he called him "the smartest player in basketball" last year. That was before the Warriors beat Carolina in the NCAA final, with Ellis giving a clinic on how to use a 6-foot-9 frame to intimate smaller foes.

Ellis' talents in college often went unappreciated by the average fan, who looked more for glittering scoring averages than for a well-timed pick and roll. Warrior player knew better; they began relying on him for leadership as early as his sophomore season, when McQuire called him the Secretariat of College forwards.

McGuire groomed players for the pros, something Ellis appreciated since his long-time ambition has been to sign a big-enough NBA contract to buy a house for his mother and sister. His Bullets pact will enable him to do that.

Al used to say you can't rush things," said Ellis. "We had this star system at Marquette, where the seniors would get the publicity and the rest of us would wait our turn. It was a fair way of doing it.

"That's why I'm not trying to rush things here.I expect to sit and wait and then hope I get a fair chance to show what I can do.

"I can get used to whatever they want. I'm not as big as I should be but I think I'm smart enough and jump well enough to help them out. I've got to be patient.

In some ways, Ellis' adjustment to proball will be a lot different than for most of the Bullet rookies. Any conventional approach to basketball by the Washington coaching staff will seem strange to him after going through McGuire's system, which banned even something as common as fast breaks.

Certainly, he will never see Motta standing on a scorer's table celebrating a victory as McGuire did one year at Notre Dame. While McGuire was holding his hands aloft giving the V for victory sign, Irish students were showering him with rolls of toilet paper.

"When Al let loose, he really let loose," Ellis said. "I still communicate with him. He's more than a friend. He told me when I came to Marquette that there would be no money there for me, but that he'd prepare me for the gold at the end of the pro rainbow. And he did."

But aren't you glad to get away from the yelling and screaming just a bit?

"You know, all coaches have got to scream," he said. "I'm expecting coach Motta to do it any day. Hey, we all do things out there that have to drive these coaches crazy.

Phil Chenier is bothered by a bad back, a chronic ailment, and probably will not be able to start practice Friday when the rest of the Bullet veterans report. But Bullet officials say the injury is nothing serious . . . Bill Cook of Memphis State was the first rookie to drop out. He left yesterday after hurting an ankle. General manager Bob Ferry had to play in order for the rookies to scrimmage.