When the NCAA voted to expand its tournament field to 48 teams this year with no restrictions on the number of teams allowed from a given conference, it was generally held that no conference would receive more than three invitations.

But now, with the start of the tournament less than six weeks away, the NCAA finds itself hearing considerable criticism from representatives of the Big Ten and the ACC, who contend that each should have at least four teams in the tournament.

The ACC currently has five teams in the top 20, Duke, North Carolina, Clemson, Maryland and Virignia. N.C.State was ranked until a week ago. The Big Ten has four top 20 teams, Ohio State, Purdue, Iowa and Indiana, with Minnesota also as a contender.

Yet it is possible that four of these 10 teams might not be included in a field of 48.

"I think in the end, when they sit down and talk about it, they'll go with the best 48 teams, regardless of conference," Big Ten Commissioner Wayne Duke said recently.

But one source on the NCAA selection committee says that isn't necessarily so. "There's a split," he said. "Some say three is enough, why invite a fourth-place team from anywhere? Others say how do you leave someone out from among Maryland, North Carolina, Duke and Virginia?"

College basketball's balance this season may work to the advantage of the conference teams. There will be many teams with between 17 and 22 wins and not that many with more. It seems highly likely that an ACC or Big Ten team with 20 wins will get a bid over an independent or second-place team from a weaker conference that also has 20 wins.

"There's no way a team like Maryland shouldn't be in the playoffs with 48 teams going," Notre Dame's Digger Phelps said after his team's 64-63 win over the Terps Saturday. "They belong in the NCAAs."

Yet if the Terps, who still face road games at Clemson, Duke and Virginia, fade from their current 6-1 mark to fourth place in the conference, they could be left in the NIT, which may have to resort to inviting high school teams to fill its 32-team field.

As Phelps points out, that wouldn't be fair. Phelps, of course, can afford to be generous. His team, like other strong independents De Paul and Marquette, has a virtual lock on a bid from day one of the season. The Irish, without conference constraints, can schedule seven or eight tough games and 19 or 20 near-certain wins.

Thus, they enter the season almost assured of 20 wins. In fact, they are so confident of an NCAA bid each season that the tournament draw is in their press guide.

No one will know for certain until March 2 what the NCAA is going to do. But if it truly wants the best 48 teams, it should invite six ACC teams and six Big Ten teams -- at least.