Donn Nelson, an assistant coach and the president of basketball operations for the Dallas Mavericks, has been a major figure in the booming development of international basketball players. He has coached international teams and coached against them and has led clinics overseas.

But Nelson's emotions will be mixed when as many as 12 international players are chosen tonight in the first round of the N.B.A. draft at the Theater at Madison Square Garden. While pleased with the global implications, Nelson will be saddened by the domestic one - that the United States may be heading toward a day when it no longer produces the world's greatest players.

"Obviously, the international market has been very good to the Mavericks, and I enjoy a great relationship with a number of coaches overseas," said Nelson, who played a role in the Mavericks' acquisition of Dirk Nowitzki of Germany. "But I'm an American."

"It's frustrating," added Nelson, the son of Dallas Coach Don Nelson, "because, being well traveled, you see other countries with a lot less in the way of natural resources, a lot less in the way of funding, a lot less in the way of talent, doing a better job of developing their young players than we are."

The impact of international players in basketball has been growing for some time, but the influx of top players is turning into a flood.