BEIJING (AP) _ Roger Federer extended his arms in triumph and began to hop. Then he embraced his doubles partner and they hopped together.

Federer had waited awhile for a big victory to celebrate, and when the chance came he was ready. He added a gold medal to his extensive trophy collection by teaming with Stanislas Wawrinka to win the Olympic doubles Saturday.

The Swiss duo beat Simon Aspelin and Thomas Johansson of Sweden 6-3, 6-4, 6-7 (4), 6-3.

For Federer the victory was a moment to savor in a frustrating year. He lost in the quarterfinals of Olympic singles, his Grand Slam total has been stalled at 12 since last September and his 4½-year reign atop the rankings will end Monday when Rafael Nadal becomes No. 1.

But he’s now a medalist for the first time in his three Olympics.

“Sort of a dream-come-true moment,” Federer said. “Maybe it comes around once in a lifetime. It’s almost disbelief, to some degree.”

Venus and Serena Williams are assured of a doubles medal, too. They advanced to Sunday’s final by beating another sibling pair, Ukraine’s Alona and Kateryna Bondarenko, 4-6, 6-4, 6-1.

The Williams sisters improved to 9-0 lifetime in Olympic doubles. They didn’t play doubles in Athens four years ago because Serena was hurt, but they won a gold medal in Sydney.

“Hopefully I’ll be able to show people a new one,” Serena said.

Like Federer, both were beaten in the quarterfinals of singles. But they’re assured of at least a silver medal in doubles.

“Obviously we would have loved to have brought home more medals for the U.S.,” Venus said. “We did the best we could. We’re not asking for more at this point. Next time we’ll ask for a little more.”

And there will be a next time, the sisters said. Both plan to play at the London Olympics in 2012.

“I’ll be in London,” Serena said.

“I definitely will be in London,” Venus said. “You know, we’ll still be pretty young.”

Venus will be 32 and Serena 30 in four years.

As for Sunday, the No. 2-seeded Williamses will play No. 4 Anabel Medina Garrigues and Virginia Ruano Pascual of Spain, who beat Yan Zi and Zheng Jie of China 6-4, 7-6 (5).

Dinara Safina and Elena Dementieva will play for a gold medal in an all-Russian singles final Sunday. Dementieva beat a third Russian semifinalist, Vera Zvonareva, 6-3, 7-6 (3), and five minutes later on an adjacent court, Safina defeated Li Na of China 7-6 (3), 7-5.

“It’s a huge moment for Russia,” Dementieva said. “I’m sure all the fans in Russia will be very happy about it.”

Mike and Bob Bryan won a bronze for the United States in doubles by beating Michael Llodra and Arnaud Clement of France 3-6, 6-3, 6-4. The medal is the first for the Bryan twins, who have won all four Grand Slam championships.

“We’re leaving China on a high,” Mike Bryan said. “We were obviously disappointed that we couldn’t make the gold medal match, but it’s going to be something really special to us to have that medal back at home.”

Novak Djokovic of Serbia won a bronze in singles by beating American James Blake 6-3, 7-6 (4). A jubilant Djokovic ripped off his shirt and threw it to the cheering crowd, along with two rackets, and waved a Serbian flag as he jogged around the court.

“To win any medal in the Olympics is a huge achievement,” Djokovic said. “Not many of the athletes get a chance to win a medal.”

Blake lost back-to-back matches after upsetting Federer and failed to medal.

“I felt like I competed hard,” Blake said. “I have to take something positive from the way I was playing this week.”

Federer will also try to stress the positive after failing to snap his singles slump in Beijing, setting his sights on the U.S. Open beginning Aug. 25. He has won that title the past four years but will be seeded No. 2 at a major event for the first time since January 2004, behind Nadal.

“Rafa played great to get it,” Federer said. “That’s what I expected and hoped for many years ago when I got to No. 1 — that if ever somebody were to take it away from me, he would have to play an incredible tennis schedule, win the biggest tournaments, dominate the game basically. I think Rafa totally deserves it.”

Not that Federer’s washed up, as he showed with some brilliant shotmaking in the doubles final, especially at the net.

Serving for a gold medal brought out the best in him. At 5-3 in the final set, he hit a service winner on the first point, then a reflex volley for a winner and another service winner. On championship point he curled in a second serve that Johansson couldn’t handle, and the Swiss were gold medalists.

“It’s not the first time this tournament or in my life I had to serve for a big match,” Federer said. “It’s basically the moment you dream of being in, even though there is so much pressure to it.”

Safina won her 15th match in a row, playing barely 12 hours after losing a doubles match that ended at 3:35 a.m. She struggled with her serve, double-faulting four times in one game, but otherwise looked fresh in the frequent long rallies.

“It wasn’t easy,” Safina said. “I didn’t sleep enough. I’m just really happy that I could put all my energy into the match and pull out the match.”

Her five wins at Beijing include an upset of top-ranked Jelena Jankovic in the quarterfinals. Jankovic, who climbed to No. 1 this week for the first time, is projected to slip back to No. 2 next week, with Ana Ivanovic reclaiming the top spot.