Six down, one to go.

That’s the sorry state of ACC men’s basketball after the first weekend of the 2007 NCAA tournament.

On a positive note, the ACC’s seven entrants were the most the league ever placed in the NCAA tournament in the same year, representing a majority of its new, expanded membership.

Every season but one between 1984 and 1998 a majority of ACC members were accorded NCAA bids, a proud sign of prowess backed up by 14 Final Four appearances in those 15 years. Since then, however, a majority got in the field just twice, in 2001 (6 of 9) and 2004 (6 of 9). Last year only a third of the ACC’s members were invited (4 of 12), the lowest percentage since 2000, raising a chorus of protest.

So the 2007 field marked both a breakthrough and an affirmation when it included Boston College, Duke, Georgia Tech, Maryland, North Carolina, Virginia and Virginia Tech.

Unfortunately, given so great an opportunity, the ACC fell flat on its face. Duke and Georgia Tech were eliminated in the first round, while BC, Maryland, Virginia and Virginia Tech went in the second.

Individually, there were good reasons each team lost, from playing against higher seeds to untimely injuries to poor free throw shooting. But the six quick exits set a modern record, or rather broke one. This is the ACC’s worst collective performance in the NCAAs since 1979, the last time the league failed to advance at least two teams to the Sweet 16.

The ACC’s 27 straight seasons with at least two Sweet 16 berths was a record of consistent excellence no other conference came close to matching, or is likely ever to duplicate.

The end of that streak calls into question whether the ACC’s much-lauded internal competitiveness in 2007 was a sign of strength or mediocrity, the regular season race a bracing two-month test or a draining ordeal that left its teams spent by the time they reached NCAA play.

This year the Pac-10 and SEC each have three squads in the Sweet 16, the Big East and Big 12 two each. Among the power conferences, only the Big 10 matches the ACC with a single entrant in the regional semifinals. Last year the Big 10 was shut out entirely, a further sign of slumping fortunes. Now that the ACC streak is over, the Big East’s six straight years with at least two Sweet 16 representatives is the longest ongoing run.

Suddenly North Carolina, the highest-seeded ACC team, stands alone in the ’07 field. Should the Tar Heels fail to reach the Final Four, that would mark another modern low point for the ACC.

The league saw no team advance to the Final Four in 2006. The last time it went two years in a row without a representative in the national semifinals was 1979 and 1980. To lend perspective to how long ago that was, Georgia Tech did not join the ACC until the 1979-80 basketball season and Mike Krzyzewski, the conference’s most senior active coach, did not arrive at Duke until 1980-81.

The ACC currently is a cumulative 6-6 in the ‘07 NCAAs. Should the Heels fall against Southern Cal on Friday, the league would finish with its first losing record in NCAA competition since going 5-6 in 1987. Should UNC suffer defeat in the regional finals, the ACC’s cumulative NCAA showing would still be its worst since 1996, when its six entrants went 6-6.

One is left to ponder whether those of us in the ACC region have an inflated sense of the conference’s strength based more on tradition and our own parochial view than is borne out by recent performance. Even if North Carolina captures a national title, this will be the second disappointing NCAA showing for the conference as a whole since its most recent expansion three seasons ago.

A few years’ results do not necessarily constitute a trend. It is too early to proclaim that expansion for football purposes and the death of round-robin play during the regular season has injured ACC basketball, the league’s signature sport. But it is not too early to wonder whether that is the case.