U.S. siblings ready to make history

Two sisters will compete in the same Games for the first time in modern pentathlon history, according to the Associated Press.

Margaux Isaksen and her younger sister, Isabella, will both represent the U.S. in Rio. This will be the third Olympics for Margaux, while Isabella will make her Olympic debut.

Australian siblings Max and Chloe Esposito will also compete in Rio.Where are the rest of the Russians?

Less than two weeks before the Opening Ceremony, the UIPM, the sport’s international federation, declared that Russia’s Maksim Kustov and Ilia Frolov were no longer eligible to compete in Rio, based on the findings in an independent report on doping by Richard McLaren.

But three other Russians-Aleksander Lesun, Donata Rimshaite and Gulnaz Gubaydullina-are still eligible to compete  in Rio. Lesun was the world champion in 2012 and 2014.

Rule change awards bonus points

The fencing bonus round will be contested for the first time at the 2016 Olympics, in addition to the fencing ranking round. The competition will be carried out in reverse order, beginning with the last-place athlete going against the next-placed athlete. The winner will receive one bonus point and advance to compete against the next best-ranked athlete.U.S. medal outlook

It has been 56 years since a U.S. man won an Olympic modern pentathlon medal, and 16 years since a U.S. woman won one.

Of the three U.S. athletes in Rio, Margaux Isaksen has the best shot at claiming a medal, after finishing fourth in London.

Hometown favorite

Brazil’s Yane Marques was the bronze medalist at the 2012 Olympics. She is hoping to claim another Olympic medal in front of her home fans.

She is a medal threat after winning the gold medal at the 2015 Pan American Games and finishing second to 2012 Olympic gold medalist Laura Asadauskaite at the 2013 World Championships.

Top modern pentathletes to watch in Rio

Nathan Schrimsher

Schrimsher was the first athlete to officially make the 2016 U.S. Olympic Team. Now he wants to become the first U.S. man to win an Olympic modern pentathlon medal since 1960.

As member of the U.S. Army’s World Class Athlete Program, Schrimsher looks up to General George S. Patton, who competed at the 1912 Games.Margaux Isaksen

This will be the third Olympics for Isaksen, who made Olympic debut in 2008 at the age of 16. She is competing for her first Olympic medal after finishing fourth in London.

Isabella Isaksen

Isabella, Margaux’s younger sister, will make her Olympic debut in Rio.Amro El Geziry

Yet another family connection for Isabella Isaksen. Her husband, Amro El Geziry, will compete for Egypt in Rio.Laura Asadauskaite

Asadauskaite is attempting to become the first woman to ever successfully defend an Olympic modern pentathlon title.