LONDON (AP) -- Five things to know about Saturday, Day 8 of the London Olympics:
-Phelps in medley relay for final Olympic race.
-Pistorius makes 400 semis; Bolt, Blake advance in 100 meters.
-Tested: U.S. men pushed in hoops win over Lithuania.
-Serena dominates Sharapova in Olympic tennis final.
-Small protest greets Syrian equestrian rider.
One more time. A relay the U.S. men have never lost.
The stage is set for quite the finale to Michael Phelps' swimming career.
Phelps will swim the butterfly leg of the 4x100 medley relay Saturday night in his final race of the London Olympics. He is planning to retire after the games.
"It's an honor to be in the last race with the greatest swimmer in history (at)MichaelPhelps. I'm sure I'll never forget it." American backstroker Matt Grevers tweeted Saturday afternoon.
Phelps began the day with three golds and two silver medals from the London Games, running his career totals to 17 titles and 21 medals overall - making him the most-decorated Olympian of all-time and adding to the anticipation for his finale.
Oscar Pistorius made his anticipated debut, and the "Blade Runner" quickly made himself at home.
Pistorius, a double-amputee who runs on carbon-fiber blades, finished second in his 400-meter heat to earn a berth in the semifinals Sunday night. He finished in a season-best time of 45.44 seconds in front of a sellout crowd at Olympic Stadium.
"I've worked for six years ... to get my chance," said the South African, who became the first amputee to compete on the track at an Olympics. "I found myself smiling in the starting block. Which is very rare in the 400 meters."
As expected, Usain Bolt advanced to the 100-meter semifinals. But there was no sign of the dazzling talent that dominated the Beijing Games.
Bolt won his race in 10.09 seconds despite struggling to get out of the blocks. His reaction time ranked sixth of the eight runners in his heat.
"I stumbled on the start," the 25-year-old Jamaican said. "I really didn't do a lot of executing."
While the sprint stars all advanced with relative ease, the U.S. men's basketball team was pushed - and then some.
The Americans trailed 84-82 with 5:50 to play, but James scored nine of his 20 points in the final four minutes to help the U.S. remain unbeaten.
"You want to get tested. The best teams want to be tested. We love the competition," James said. "I think we've got some of the greatest competitors in our league, in this world, so you want to have a game where you feel like you were tested, and we had that today."
Linas Kleiza scored 25 for Lithuania, which shot 58 percent and outrebounded the U.S. 42-37.
There was no such test for Serena Williams, who blew away the field at Wimbledon.
The American star became only the second woman to achieve a Golden Slam, routing Maria Sharapova 6-0, 6-1 in the most lopsided women's final in Olympic history.
The victory completed a remarkable run of domination by the No. 4-seeded Williams, who lost only 17 games in six matches en route to her first singles gold medal. She went 13-0 this summer at the All England Club, where she won her fifth Wimbledon title a month ago.
"I was so focused here," she said. "I remember I was serving and I was thinking: 'Serena, this is your best chance to win a gold medal. You're at Wimbledon, you're on grass, you play great on grass, pull it together, just win this.' And that's what I thought about."
Also Saturday, a dozen people opposed to the Syrian government staged a small demonstration to protest the presence at the Olympics of a Syrian equestrian rider whose father is under U.S. sanctions for supporting President Bashar Assad.
Ahmad Saber Hamsho told The Times of London in June that the Assad regime was "only protecting people from guys with weapons." Rebels have fought the regime for 17 months in an uprising that has claimed 19,000 lives and turned into a civil war.
Hamsho competed in the show jumping individual qualifier event, producing a clear round on a horse called Wonderboy. Protesters outside the gate at Greenwich Park handed out leaflets and "Freedom for Syria" stickers.
Hamsho said he was representing the country, not anyone in particular, in the equestrian ring. He said he didn't want to talk about Syrian politics and dismissed the protesters as "totally stupid."
Jay Cohen can be reached at http://www.twitter.com/jcohenap