* U.S. take on Spain in basketball showdown
* Men's marathon and boxing among last medals up for grabs
* British pop royalty to sparkle in closing ceremony
By Matt Falloon and Larry Fine
LONDON, Aug 12 (Reuters) - The United States' Dream Team will defend their Olympic men's basketball title on Sunday as the London 2012 Games, blessed with the sprint pyrotechnics of Usain Bolt and the record-breaking legacy of swimmer Michael Phelps, draws to a close.
Peppered with household names from the glitzy world of NBA such as LeBron James and Kobe Bryant, the U.S. will do battle with a dangerous Spanish team looking for revenge in a repeat of Beijing's final.
"We all know what's on the line," said U.S. player Kevin Durant. "They're going to come out and give us their best shot. We got out work cut out for us."
A victory on the court is likely to cement the Americans' place at the top of the overall Olympics medals table. The U.S. team has 44 golds so far, above China with 38 and Britain on 28, well above their Beijing tally of 19.
The men's marathon, mountain biking, wrestling, volleyball and a flurry of boxing finals will help to round off the two-week extravaganza of sport before some of Britain's best-known pop acts, including The Who and George Michael, close the show.
The U.S. basketball team will find it hard to top Saturday night's spectacle on the track when Bolt led a Jamaican quartet to 4x100 metres gold in world record-breaking time and the hosts' Mo Farah claimed another title - this time the 5,000m.
Bolt adds the relay title to the 'double double' he won in the 100m and 200m, defending both after his Beijing triumphs and writing his way into Olympic history as one of the finest - and zaniest - sprinters the world has known.
As he crossed the line, Bolt cupped his hands in an 'M' shape above his head - a nod to Farah who had earlier run away from the pack to win Britain's first men's 5,000m gold.
Farah, contributing to the hosts' biggest medal haul in more than a century, is the seventh man to win the 5,000m and 10,000m titles at the same Olympics.
The final few moments of Olympic glory in track and field brought a close to an eventful penultimate day of the Games in which startling athletic prowess did not completely dominate the headlines.
Syrian athlete Ghfran Almouhamad, who competed in the women's 400 metres hurdles, was the 11th athlete to be thrown out of the Games since the start of the Olympic period, which began on July 16, after testing positive for a banned substance.
The 10-strong Syrian team has attracted considerable media attention during London 2012, less for its sporting achievements than the bloody conflict raging at home between rebels and forces loyal to President Bashar al-Assad.
The Spice Girls, One Direction, George Michael and The Who are expected to perform in the closing ceremony as London prepares to bid goodbye to what the Guardian newspaper dubbed the "feelgood Games".
Games chief Sebastian Coe declined to compare London with other Olympics, but said simply: "I'm pretty pleased with the way we've delivered."
"Party, party, party," he told a news briefing when asked to describe the closing concert ending a drama-filled few weeks.
After weeks of concerns about how the capital's creaking transport system would cope with a huge influx of tourists and fears that not enough security staff were being recruited, the Games have so far passed by relatively trouble free.
A scandal over empty seats at several Olympic events also blew over, especially once the track and field showcase kicked in and drew in capacity crowds.
Forecasters point to a warm and dry day in London to bring to a close a festival that has helped to lift the gloom in recession-hit Britain.
Prime Minister David Cameron has tried to use the Games to woo investment to Britain, hoping it would give the economy a much needed boost, although some London businesses complained that warnings about overcrowding from the Games had driven customers away.
As well as a "hit list" of more than 30 popular songs, the closing ceremony will feature thousands of athletes and performing volunteers as well as a section devoted to the next summer Olympic hosts, Rio de Janeiro.
"I think it's a gift that we've got Rio next because their eight minutes is so wonderful and really full of that samba beat," artistic director Kim Gavin said of the 2016 hosts.