For much of the past half-century, the ACC basketball landscape usually took on a familiar appearance when March arrived, with games between North Carolina schools determining which team from that state would win the regular season title. While perhaps only temporary, this season has marked a power shift in what has long been a Carolina-dominated conference.

In the regular season's final week, the top four schools include two teams, Virginia Tech and Boston College, that weren't even in the conference three seasons ago and another, Virginia, that has not won the regular season title since 1981. North Carolina remains tied for first place, and Duke has been hot of late, but both traditional powers have looked vulnerable during conference play.

"With the success of Boston College, Virginia Tech and Virginia, it is" less of a Carolina-dominated league, Maryland Coach Gary Williams said. "Duke and Carolina have been beaten. A lot of times, this time of year they are 14-2 or 15-1 [ACC records] for some of the Carolina teams. It's not that way this year. I think everyone feels some confidence in their ability when they play those teams."

Tonight's game between No. 24 Maryland and No. 14 Duke is a much-anticipated showdown at Cameron Indoor Stadium, but it is a contest that could help decide fifth place in the league, not first. The week's biggest game will occur tomorrow in an unlikely setting, Charlottesville, where Virginia and Virginia Tech, two schools tied for first, will clash.

"It is kind of neat," Virginia Coach Dave Leitao said. "Traditionally other schools have kind of controlled the mind-sets of people in this league, particularly this time of year, so it's a tribute to both schools, and it should be a fun night."

Nine of the ACC's past 10 regular season champions were schools from North Carolina. And 12 of the past 13 ACC tournament champions were from that state. The exception in both cases was Maryland, which won the regular season title in 2002 and the tournament championship in 2004.

There are other signs of change. Tampa will host next week's ACC tournament, which has been staged in the state of North Carolina 15 of the past 17 years.

"To move it around makes sense and is healthy for the tournament," Georgia Tech Coach Paul Hewitt said. "Maybe have it someplace in Virginia sometime would be a good thing."

Another difference is that most of the conference's best players play at schools outside the state of North Carolina. In each of the past six years, at least three players from North Carolina schools earned first-team all-conference honors. This season, there could be as few as one, North Carolina's Tyler Hansbrough, on the first team. In conference games, Hansbrough is the only player from a North Carolina school who ranks among the top eight in scoring.

One reason for the disparity is because the league's top four schools outside the state of North Carolina are the conference's most experienced teams. Seniors have made at least 50 starts this season for Boston College, Maryland, Virginia and Virginia Tech.

Conversely, Duke has not started a senior in a game this season, and North Carolina has had seniors make 29 starts. The Blue Devils are primarily led by sophomores, while the Tar Heels get an average of 44 points per game from freshmen.

As a result, Virginia Tech has beaten North Carolina twice and Duke once. Virginia beat Duke. And Maryland has beaten North Carolina and has a chance to sweep the Blue Devils in the regular season tonight.

The Tar Heels, however, will remain in position to earn a top seed in the NCAA tournament if they can finish the regular season strong. On Sunday, they host a resurgent Duke team that has recovered from its first four-game losing streak in 11 years. The Blue Devils have not lost since a 12-point defeat at Maryland on Feb. 11.

"When we lost four games in a row, it is not like we had four losing performances worthy of a loss," Duke Coach Mike Krzyzewski said. "In three of the four games, we played winning basketball but were not able to win. Against Maryland, we did not play winning basketball."

The two other North Carolina schools, North Carolina State and Wake Forest, are tied for last place in the ACC, although each has proven to be capable of being competitive against an upper-echelon team on a given night.

"This league, it's hard to predict what is going to happen," Boston College Coach Al Skinner said. "Look what Maryland has been able to do of late; they look like gangbusters right now. This league is unforgiving. I think every team in this league has had some losses where you've said, 'Oh, are we going to win another game?' And you turn around and have a great game."