VANCOUVER, JULY 28 -- Chris Evert and Pam Shriver breezed to straight-set victories today to enable the defending champion United States team to defeat unseeded Japan and advance to the second round of the Federation Cup.

It is the 25th straight year the United States has reached at least the second round of the women's equivalent of the Davis Cup.

Shriver, playing her first Cup singles match as a replacement for injured Martina Navratilova, appeared nervous and confused in the first set as Iakiko Kijimuta recovered from a 5-2 deficit to force a tie breaker. But Shriver, No. 5 in the world, won the tie breaker, 7-0, en route to a 7-6, 6-1 victory.

"I guess I was a little nervous, especially in the first set," Shriver said. "She got to know where I was going to hit the ball after a while, but I changed that. Fortunately I got a very good tie breaker -- I don't remember ever winning 7-love. And in the second set I just rolled."

Evert dominated Etsuko Inoue, 6-2, 6-4, on the hard court surface of the Hollyburn Country Club, then teamed with Zina Garrison to give the United States a 3-0 sweep by winning the doubles, 6-2, 7-5, over Kijimuta and Inoue.

Evert, in her first tournament since she lost a Wimbledon semifinal to Navratilova three weeks ago, said, "I have to work my way into this. But I was pleased with my concentration."

In other first-round matches, fourth-seeded Bulgaria beat Greece, 2-1; fifth-seeded Australia beat Denmark, 3-0; eighth-seeded Italy defeated Belgium, 3-0; Britain topped Chile, 3-0; Spain defeated Jamaica, 3-0; France beat Austria, 3-0, and Indonesia defeated Ireland, 3-0.

The United States, winner of 12 of 24 Cups, has remained the favorite despite the withdrawal of Navratilova, the world's No. 1 player, who sprained her left ankle playing basketball last week.