U.S. Davis Cup Captain Tony Trabert would like to regard next weekend's North America Zone finals against South Africa solely as the first of four encounters his team must win in order to regain the cup this year. But he is obviously aware that many people view these matches more as a political than a sporting event.

The U.S. team of Harold Solomon, Vitas Gerulaitis, Fred McNair, who is from Chevy Chase, Sherwood Stewart, and sparring partners Sandy Mayer and Larry Gottfried will begin practise tomorrow afternoon in Nashville for the controversial matches, scheduled next Friday evening and Saturday and Sunday afternoon at Vanderbilt University's Memorial Gymnasium.

Meanwhile, the civil rights and anti-apartheid groups that have been picketing the Vanderbilt administration building for two weeks are completing six weeks of political mobilization. They plan massive demonstrations to protest South Africa's policy of racial separation.

The demonstrations are expected to be peaceful and orderly, but Trabert noted that "we will be taking what we consider to be appropriate security precautions."

Last April, when the U.S. defeated South Africa, 41, in Newport Beach, Clif., several hundred demonstrators protested South Africa's participation. On the second day, during the nationally televised doubles match, two protestors ran out and spilled oil on the court. Trabert tried to stop them and hit one with a tennis racket.

With the involvement of large, influential civil rights groups for the first time, much bigger demonstrations are expected in Nashville, but no attempts to disrupt play are anticipated. No television coverage is scheduled.

When Ray Moore, South Africa's top-ranked singles player, withdrew from his country's team 12 days ago, he said one of the reasons for his action was that the contest "is no longer a sporting event."

U.S. Ttnnis Association (USTA) and Vandervilt officials are determined, however, to adhere to the increasingly beleaguered position that sports and politics should not mix and that a tennis court is not a political forum.

"I think this is a sporting event, and we'll do everything we can to play in that spirit and make it good tennis for everyone," said Trabert, who has named Solomon and Gerulait-is to play the four singles matches and McNair-Stewart as his doubles team for the best-of-five-match series .

"We hope the political aspects are minimal. If there are people and groups who want to demonstrate peaceably to try to get their mesage across, they certainly have a right to do that."

The withdrawal of Moore, who has beaten Gerulaitis in their last two meetings, greatly diminished South Africa's already shaky chances of winning the series. Nevertheless, Trabert says he expects "a very tough match."

BOb Hewitt and frew McMillan, arguably the best doubles ream in the world, will be favored to win the doubles point, but South Africa will be a decided underdog in all the singles matches. Byron Bertram and Bernie Mitton (who has a 2-1 career record against Solomon) are expected to play.

The U.S. has won the cup 24 times since 1900, but not since 1972. In the last four years, it has failed to win the American Zone, falling to inspired performances by Colombia, Mexico twice, and Argentina.

The winner of the Nashville series advances to the American Zone final against the victor of the South Section final: Chile vs. Argentina.

Peter Lamb, a Vanderbilt sophgmore of nixed race, and Robble Venter, a white UCLA freshman, are training as members of the South African squad, but are not on the four-man playing team. Selection of Lamb, the first nowhite named to the South African squad, was denounced as "tokenism" by the groups opposed to South Africa's participation.

Jan. 30, a coalition of civil rights groups, including the National Association for the Advancement of Colored People (NAACP).National Urban League, and American Committee on Africa, launched a major campaign opposing the U.S.-South Africa meeting.

These and other organizations opposed to sports ties with South Africa brought pressure on the USTA, Vanderbilt, and political figures to to cancel the matches.

NAACP executive director Benjamin Hooks promised "the biggest demonstrations this country has seen since the 1960s" in nashville. Charles Kimbrough, president of the Nashville NAACP chapter, predicted that more than 40,000 people would participate.

The USTA position has been that, although it does not condone apartheid, it must abide by international tennis rules and play any country drawn against it, regardless of the politics of its government. Under Davis Cup rules, any nation that enters the draw and then defaults for political reasons is subject to an automatic two-year suspension.

USTA president W.E. (Slew) Hester has pledged that the USTA will work for the voluntary or forced removal of South Africa from the Davis Cup in 1979.

The controversy has split the Nashville community and the Vanderbilt campus, but the university administration has remained firm in its position that refusal to host the matches - for which it contracted before South Africa was determined as the opponent - would violate its long-held "open forum" policy.

"Neither Vanerbilt as an institution, not I personally, nor any of the university's personnel insofar as I know, sympathizes in any way with the policies of apartheid," Chancellor ALexander Heard said. "The interest of Vanderbilt's Department of Athletiacs in this event, since negotiations began last September, has been in support of international tennis as part of Vanderbilt's tennis program.

"... Tennis play by a taeam from South Africa on our campus does not represent support or endorsement of apartheid by the university or its officers any more than the appearance of controversial speakers on campus constitutes support of what thosespeakers say. Davis Cup competition is a sporting event. If it is cast as a political one, the fundamental policy of open forum would be even more applicalbe."