Ali Carter of England looks on during the match against Stuart Bingham of England during the 2011 China Open at Beijing University Students Gymnasium on March 30, 2011 in Beijing, China.

Alejandro Simon of Spain prepares to serve during their Preliminary Phase Pool E match against Canada during the VISA FIVB Beach Volleyball International at Horse Guards Parade on August 10, 2011 in London, England. (Photo by Scott Heavey/Getty Images)

Russian Police detain opposition supporters during a “March of Millions” protest rally against Vladimir Putin's return in Moscow, Russia on May 6, 2012. Over 650 people were arrested including opposition leaders. (Photo by Dmitry Schedrin, Rustem Adagamov, Andrey Stenin)

Arizona Cardinals cheerleader Claire Thorton, center, smiles as Air Force Capt. Eric Straub proposes to her during the first half of an NFL football game against the Washington Redskins, Sunday, October 12, 2014, in Glendale, Ariz. Thorton accepted the proposal. (Photo by Rick Scuteri/AP Photo)

Israeli soldiers detain a protester during a demonstration by Palestinians protesting against the Israeli-built West Bank separation barrier and calling for the right of return for Palestinian refugees, in the northern West Bank city of Tulkarem, on May 31, 2014. (AP Photo/Nasser Ishtayeh)

A protester with his face smeared with soot from burning barricades stands in the Musaga neighbourhood of Bujumbura on May 6, 2015. Government and opposition rivals are meeting in Burundi in a bid to end deadly demonstrations against a third term bid by the president, as regional foreign ministers arrived to add pressure. (Photo by Phil Moore/AFP Photo)

A protester holding a torch runs past police (not pictured) trying to stop the protesters from marching in a rally organised by a 30-party alliance led by a hardline faction of former Maoist rebels, who are protesting against the draft of the new constitution, in Kathmandu August 15, 2015. The group says that the draft is not inclusive and does not protect the rights of the marginalised and underprivileged groups in the country. (Photo by Navesh Chitrakar/Reuters)

Serena Williams of the U.S. serves during her first round match against Italy's Camila Giorgi at the Australian Open tennis tournament at Melbourne Park, Australia, January 18, 2016. (Photo by Jason O'Brien/Reuters)