Russian stars who could miss the Rio Olympics

MOSCOW  — The International Olympic Committee says it is exploring the legal options for a possible ban of the entire Russian team from next month's Olympics in Rio de Janeiro as a result of the country's repeated doping scandals. Russia finished fourth in the gold medal table at the 2012 Olympics in London and third in the overall medal table. Its absence in Rio would shake up both tables. Here are five Russian stars who could miss out:

Aliya Mustafina

She led the Russian gymnastics team which narrowly failed to beat the U.S. to gold in the women's all-around in 2012 and also won individual gold in the uneven bars. While Mustafina has been plagued by injuries since, she bounced back with two European championship gold medals last month. Russia has arguably the world's richest tradition of excellence in gymnastics, and if its athletes aren't in Rio, the U.S. and China will benefit in the medal table.

Yulia Efimova

One of the world's top breaststroke sprinters, Efimova spearheads the Russian swim team for Rio despite previous brushes with the anti-doping authorities. She bounced back from a drug ban to win 100-meter gold at last year's world championships in a fiercely competitive race with her longtime rival, Lithuanian teenager Ruta Meilutyte, who would become the hot favorite for gold if Efimova is forced to miss Rio. Efimova missed four months this season after testing positive for the banned substance meldonium but was given a reprieve and won the 200 at her comeback meet in Los Angeles on Sunday.

Yelena Isinbayeva

The world record holder in the pole vault and a two-time Olympic gold medalist, Isinbayeva would compete at her fifth games in Rio, but she faces extra obstacles to get there. Russia's track and field team is already banned from the games due to widespread doping, and Isinbayeva's hopes rest on a successful appeal at the Court of Arbitration for Sport. She represented Russia's athletes at a crucial CAS hearing on Tuesday in Switzerland and even posted a selfie online from inside the closed session. Her absence in Rio would help Brazilian, Greek and U.S. athletes, among others.

Nataliya Ishchenko

With three Olympic and 19 world championship gold medals to her name, Ishchenko typifies Russia's total domination of synchronized swimming — it's won every Olympic event this century. If no Russians compete in Rio, China and Spain would fight for the two gold medals on offer. Russia is similarly dominant in another female-only Olympic sport, rhythmic gymnastics, where former Soviet nations Ukraine and Belarus usually compete for the silver behind Russia's winners.

Maxim Mikhailov

Top scorer when Russia won the men's volleyball competition at London 2012, Mikhailov would be a formidable opponent in Rio. Host nation Brazil had to settle for silver four years ago but is fired up for a gold medal in front of its home crowd. The absence of the Russian team would make that mission significantly easier.