LONDON — Five things to know about Thursday, Day 13 of the London Olympics:
—American Mitchell breaks leg, completes relay segment.
—Pistorius' South African relay team advances to 4x400 relay on appeal.
—Too good: American Shields claims Olympic women's boxing gold in style.
—U.S. women wear down Australia to make women's basketball final.
—Olympic official to AP: IOC to strip Tyler Hamilton of 2004 gold, give it to Russia's Ekimov.
Manteo Mitchell kept going after he felt something pop in his left leg halfway through the opening lap in the 4x400-meter relay preliminaries.
Turns out this was one impressive run.
Mitchell finished in 46.1 seconds and helped the Americans tie for first with the Bahamas in 2 minutes, 58.87 seconds Thursday. A few hours later, doctors told him he had a broken leg.
The relay final is set for Friday. The Americans have won the last eight long relays they've entered at the Olympics.
"I figured it's what almost any person would've done in that situation," Mitchell told The Associated Press.
Double-amputee Oscar Pistorius and his South African teammates also reached the 4x400-meter relay final.
The man known as "Blade Runner" because of his carbon-fiber prosthetics will get a chance to run for an Olympic medal after officials accepted South Africa's protest over a collision and awarded an extra spot in the final. Pistorius already is the first amputee to compete on a Summer Games track.
Caster Semenya, Pistorius' countrywoman, won her 800-meter semifinal in 1:57.67 to move one step closer to an Olympic medal three years after being forced to undergo gender tests.
Those preliminaries came hours before the main event at Olympic Stadium: the 200-meter showdown featuring Jamaican's speedy duo of Usain Bolt and Johan Blake.
In the boxing ring, Claressa Shields danced, brawled and even stuck out her tongue. The exuberant American teenager also managed to win the first middleweight gold medal in the new Olympic sport.
Irish lightweight Katie Taylor and British flyweight Nicola Adams also won gold at the landmark tournament, claiming the first Olympic titles in a growing women's sport that was banned in Britain until 1996.
The five-day event was one of London's biggest hits. And even amid the sea of Irish fans cheering Taylor's every move, the 17-year-old Shields was one of the breakout stars of the games.
Shields' power and elusiveness were far too much for 33-year-old Russian Nadezda Torlopova, nearly twice Shields' age and half her speed at times. Shields won fairly easily, 19-12.
The U.S. women's basketball team faced its first challenge of the Olympics, and found a way to advance to the final.
Trailing early in the second half, coach Geno Auriemma turned to his Olympic rookies and the group — led by Tina Charles and Lindsay Whalen — pressured Australia into turnovers and bad shots. That led to a pivotal scoring run in the third quarter of an 86-73 victory.
The Americans, seeking a fifth straight gold medal, will meet the winner of the France-Russia semifinal.
Lauren Jackson finished with 14 points for Australia.
The IOC is set to formally strip American cyclist Tyler Hamilton of his gold from the 2004 Athens Games and reassign the medals after his admission of doping, according to an Olympic official familiar with the case.
With the eight-year deadline approaching, the official told the AP that the IOC executive board will meet Friday to readjust the standings from the road race time trial and award the gold to retired Russian rider Viatcheslav Ekimov.
The official spoke on condition of anonymity because the decision hasn't been announced yet.
After years of denials, Hamilton told CBS' "60 Minutes" last year that he had repeatedly used performance-enhancing drugs. The IOC asked for documents from the U.S. Anti-Doping Agency before reallocating the medals.
The gold will now go to Ekimov, a former teammate of Hamilton and Lance Armstrong.
American Bobby Julich will be moved up from bronze to silver, and Michael Rogers of Australia from fourth to bronze.
The rest of the Olympic action Thursday:
Eva Risztov of Hungary led most of the way in a grueling open water marathon at Hyde Park, holding off a desperate bid to chase her down by American Haley Anderson.
The big crowd was hoping for a gold medal from world champion Keri-anne Payne, but the British swimmer finished fourth.
Risztov beat Anderson by four-tenths of a second after nearly two hours of racing around The Serpentine. The winner climbed out of the water, smiling and looking fresh. She even flexed for the big crowd.
Risztov retired from swimming after the 2004 Olympics, upset with her results and tired of the pool. She eventually decided to give open water a try, and it sure worked out in a big way.
Martina Grimaldi of Italy got the bronze in the 10-kilometer race.
Russia led the technical routine of the team event — as expected.
Russia has won this event at the past three Olympics. Featuring Natalia Ishchenko and Svetlana Romashina, the pair that won the duet Tuesday, it collected a near-perfect 98.1 points.
The favorites competed to a Russian dance routine composed by Denis Garnizov, as Prince William's wife, Kate, looked on from the crowd.
China was next with 97.0 points and Spain finished third with 96.2 points.
Medals will be handed out after Friday's free routines, with points from both days added up.
The quartet of Tate Smith, Dave Smith, Murray Stewart and Jacob Clear gave Australia a lift with a surprising wire-to-wire win in the men's 1,000-meter K-4.
It was Australia's first team gold in canoe sprint — and took its overall tally in London to six after wins by cyclist Anna Meares, 100-meter hurdler Sally Pearson and sailors Nathan Outteridge and Iain Jensen in the past three days.
Germany collected two more victories, with Tina Dietze and Franziska Weber taking the women's 500-meter K-2 and Peter Kretschmer and Kurt Kuschela winning the men's double canoe sprint 1,000.
Danuta Kozak won her second gold of the regatta for Hungary, grabbing the top spot in the women's single kayak 500-meter sprint.
ELSEWHERE IN LONDON
Charlotte Dujardin of Britain won the individual dressage gold medal on Valegro, scoring 90.089 percent in the deciding grand prix musical freestyle which featured Olympic theme music and chimes from Big Ben. Adelinde Cornelissen of the Netherlands, riding Parzival, won silver, while Laura Bechtolsheimer of Britain on Mistral Hojris took the bronze. ... The men's 470 medals race was abandoned because there wasn't enough wind on the nicest day of the sailing regatta. It was rescheduled for Friday.
Jay Cohen can be reached at http://www.twitter.com/jcohenap