George Mason continues to walk the fine line on the negative side of playing a college basketball team that is nationally recognized.

The Patriots lost to Duke tonight, 90-79, at Cameron Indoor Stadium in a game in which forward Carlos Yates scored 35 points and George Mason had a good chance to win until the final minute.

"I don't know when that breaking point is going to come," George Mason Coach Joe Harrington said a few minutes before the game. "I don't know if tonight's the game, but we're working on it."

Mason (6-3) used its quickness to maximum efficiency and held the much bigger Blue Devils to a standoff in rebounding in taking a 47-38 lead early in the second half.

But three factors kept the Patriots from making the breakthrough that Harrington and his players say will make George Mason a recognizable name in Division I basketball.

At that point, Duke began playing better and harder. Rebounding was no longer a standoff, the Blue Devils (5-4) making several key offensive rebound baskets. Yates also was called for his third foul. The effect was evident right away.

One possession after Yates' third foul, Mason began playing more zone defense, but did not play it well. Harrington and guard John Niehoff said that foul was not the main reason Mason began playing more zone, which allowed Duke to play a classic inside-outside game resulting in open jump shots.

"We felt that we could do well in a zone, but we didn't," said Niehoff, who led George Mason's offense and also scored 14 points. "We didn't talk and we didn't pick people up."

Yates said his third foul "just changed the momentum of the game. For us it had a mental effect, playing them on their own floor. We're a quick team and when we allowed them to set up against our zone, it allowed them to play to their strength, pounding it inside."

It was 56-50, George Mason, with 12:23 to play when Duke's offense became sharp and Mason lost some of its fine-tuning. In its next seven possessions, Duke scored on long, open jump shots five times and tied the game at 63. Especially accurate for the Blue Devils were guards Chip Engelland, a senior from whom it is expected, and David Henderson, a freshman whose 18 points more than doubled his season's average.

It was in the next four possessions that George Mason failed against Duke's physical, man-to-man defense. The Blue Devils twice converted offensive rebounds into baskets.

George Mason remained within five points with less than two minutes to play, and forced the Blue Devils into putting the ball up for grabs against a press. A jump ball was called, but Duke retained possession on the alternate possession rule.

In this span, Niehoff twice tried to force shots over Duke's 6-foot-9, 6-9, 6-8 front line instead of going into his team's offense.

Yates' 35 points were scored against five defenders, and none could stop him. He made 10 of 16 shots and all 15 free throws, and also had six rebounds and five assists. Henderson, a freshman guard, did the best job against him, mainly because of his quickness.

Yates, a 6-5 sophomore, went into the game averaging 25.8 points per game. The 35 equaled his career high. He has not scored less than 20 points in nine games this season.

After the game, it was learned that junior Andy Bolden, starting point guard for the Patriots, will be academically ineligible for the remainder of the season. Bolden was the ECAC South rookie of the year in 1980-81. Meanwhile, center Mike Shannon, who was ineligible the first nine games, has regained his eligibility.