U.S. men win the 4x400 relay to conclude 2015 world championships

The United States men won gold in the 4x400-meter relay—their lone gold medal on the track. Team USA finished the 2015 IAAF World Championships with a total of 18 medals.

The United States men captured their lone world-championship medal on the track at the 2015 IAAF World Championships in Beijing. LaShawn Merritt anchored the men's 4x400-meter relay team to a 2:57.82 for the victory and extended the team's streak to six consecutive world championship gold medals in the event.

The United States received the baton heading into the final lap with Trinidad and Tobago at their side. Merritt ran a personal best of 43.63 in the 400-meter final on Wednesday, but fought off a challenge by Jamaica's Javon Francis with 200 meters to go. In the final straightaway, the 2013 world champion Merritt pulled away from Jamaica for the win.

With the victory, Merritt surpassed Carl Lewis as the most decorated U.S. man at a world track and field championships with 11 medals. He entered the 2015 world championships with nine before taking silver in the men's 400 meters and then gold in the relay on Sunday night.

Watch the American men extend their world championship winning streak below:

Women's 4x400-meter final: A blistering 47.7-second split by Allyson Felix on the third leg of the women's 4x400-meter relay gave the Americans the lead going into the final lap, but Francena McCorory was passed on her right side in the final 50 meters by Jamaica's Novlene Williams-Mills. Jamaica took gold in 3:19.13, the fastest time of the year. The U.S. settled for silver as Great Britain nabbed the final medal in 3:23.62.

“I think this one hurts more because we have such a rich history in the 4x4,” Felix told reporters after the race. “It's not often that we lose it but it's also a lot of motivation for next year.”

Men's high jump final: Canada's Derek Drouin won a three-man jump-off by clearing the 2.34-meter height against China's Guowei Zhang and Ukraine's Bohdan Bondarenko. Drouin's gold adds to his collection of a 2012 Olympic bronze medal, a '13 world championship bronze medal and '15 Pan American Games gold medal.

Watch Drouin's winning jump below:

Women's 5,000-meter final: Ethiopians swept the podium, but 1,500-meter gold medalist and world-record holder Genzebe Dibaba was not the first across the finish line. After three rounds of the 1,500-meters and one round of the 5,000-meter run, Dibaba faltered toward the end of the race and was unable to close the gap on Almaz Ayana, who took the lead shortly after two kilometers. Ayana crossed the finish line in 14:26.83 for a new championship record, which was previously held by Genzebe's older sister, Tirunesh. 

Senbere Teferi finished second for silver in 14:44.07. Genzebe Dibaba took third for bronze in 14:44.14. It was her first loss of the year in any event.

Nicole Tully, the lone American in the final, finished 13th in 15:27.42. 

Men's 1,500-meter final: Being in 10th place with one lap remaining was no problem for Kenya's Asbel Kiprop as he kicked about a 52-second last lap to come away with the 3:34.40 victory over compatriot Elijah Manangoi. Abdalaati Iguider finished in 3:34.67 to edge out Olympic champion Taoufik Makhloufi off the medal stand. 2011 bronze and '13 silver medalist Matthew Centrowitz finished in eighth place with a 3:36.18 performance as the top American. 2012 Olympic silver medalist Leo Manzano and former NCAA standout Robby Andrews finished in 10th and 11th place, respectively. 

Kiprop won his third world title and may head to the 2016 Summer Olympic Games in Rio de Janeiro as the reigning Olympic and world champion much like he did in '12. 

• WATCH: Usain Bolt pull off the gold medal treble with Jamaican 4x100 win

Women's javelin: On the final throw of the night, Germany's Katharina Molitor recorded a 67.69-meter throw to win gold. Her previous best finish at the world championships was a fifth-place finish in 2011. 

Medals: The United States finishes the world championships with 18 medals, its fewest total since 2003, as the team collected six gold medals, six silver medals and six bronze medals. The team won 25 medals at the 2013 world championships in Moscow. Kenya finished on top of the medal table with 16 medals, including seven gold.​

Next championships: Track and field will return to action at the outdoor global stage in 347 days at the 2016 Summer Olympics in Rio de Janeiro. The world indoor championships will be held in Portland in March. The IAAF flag was handed over to the Great Britain as London will host the 2017 IAAF world championships.