BEIJING, Aug. 14 (Xinhua) -- Beach volleyball defending champions Misty May-Treanor and Kerri Walsh continued their winning streak on Thursday and finished first in women's group B.

The U.S. pair never trailed in their third preliminary, a match with Nila Ann Hakedal and Ingrid Torlen, ending the match 2-0 (21-12, 21-15).

Walsh said after the match the Norwegian pair also made problems for them in the match. Their serves were strong, she said.

Walsh said they were confident to keep the gold medal they captured four years ago in Athens after the three preliminary victories. In the next matches they would play better, said the 1.90-meter Walsh, who will have her 27th birthday on Friday.

Dubbed as "queens of the beach", the American duo has not been defeated in a single match since last August.

Men's beach volleyball legend and three-time Olympic champion of the United States Karch Kiraly also prized the partnership of May-Treanor and Walsh "the best ever."

"We want to win (again)," May-Treanor has said. "We put pressure on ourselves," May-Treanor said before the Olympic Games opened.