BOSTON -- Only three games into the season, Dee Brown already has established himself as somewhat of a Boston Celtics anomaly.

As a rookie guard, he is playing and not watching when games are being decided. And the team seems, even at this stage, to be interesting, perhaps better than many thought.

The history of Celtics rookies, until recently, has been twofold: The great ones played and the other ones, especially guards, waited unless the franchise was in a downward spiral.

Sam Jones averaged 10.6 minutes his rookie year, K.C. Jones 12.4. Even the redoubtable Bill Sharman played just 22 minutes a game in his first Celtics season.

In the 1980s, only two rookies started with any regularity: Larry Bird (because he's Larry Bird) and Brian Shaw (because the team had been one loss from the lottery).

Given Boston's unpredictable backcourt situation, there was little doubt Brown would plunge into the DNP-CD category. However, he not only has played -- an average of 22 minutes a game -- but he was on the floor when the Celtics made critical, late-game runs in New York and Chicago to erase big deficits.

"There's no experience like playing experience, especially at this level," Brown said yesterday. "You can sit and watch Isiah {Thomas} and {Mark} Price all you want, but until you run up on them, it's a different story.

"You don't get experience sitting on the bench. You get experience by playing," Brown said. "If I was sitting down, yeah, I'd get experience because I was there. But I wasn't on the court. I don't know that pressure."

Shaw can relate. He had a fine exhibition season in 1988, but he also had Dennis Johnson, Danny Ainge and Jim Paxson theoretically ahead of him on the depth chart.

However, on opening night, the Celtics were getting a scare from the Knicks. Rookie coach Jimmy Rodgers pulled Ainge in the final five minutes and went with Shaw. He stayed with the rookie in overtime and Boston prevailed.

That, of course, did wonders for Shaw's confidence. Asked about giving Brown meaningful minutes right out of the blocks, Shaw said: "These games will age Dee a lot. And it has to help him because he not only was in there, but we came back and won."

Brown is in there because he can apply defensive pressure and engineer the fast break. But occasionally will play out of control. He is averaging a turnover every 7.3 minutes, highest on the team (Bird is next at 8.4 minutes).

Against the Bulls, he played wildly in the first half. Assistant Don Casey, ex-Clippers coach, went over to Brown during a break and reminded him of a conversation the two had had at rookie camp.

"Basically, he asked me to help him avoid the mistakes that {Clipper} Gary Grant made," Casey said. "Gary Grant had a big-play mentality and that sometimes hurt him. So I reminded Dee about that and just told him to get involved. He listens and he's instinctive and he doesn't often make the same mistake twice. To me, that's the sign of a person going onward and upward."