The opera world continues to bloom at sporting events, with Placido Domingo recently announcing that he will be performing before the World Cup finals in Brazil.

The opera star is the latest in a line of such singers to perform at prestigious sporting events this year. In February, American soprano Renee Fleming became the first opera singer to perform the national anthem at the Super Bowl. Fleming not only astonished the opera world, but also garnered new followers and grew in her status as the most popular soprano in the world.

Later that month, Russian soprano Anna Netrebko performed the Olympic hymn. Netrebko's performance was not the first time an opera singer had sung the song. The performance also was not as publicized and did not have the same effect in the US. Nonetheless, Netrebko garnered more followers in Europe and now is rumored to be scheduled to perform to begin the 2018 World Cup, which will take place in her native Russia. In 2010, she was one of the ambassadors on hand to receive notice that Russia would host the tournament.

The sports arena also saw Russian soprano Hibla Gerzmava perform at the closing ceremony of the Olympics. However unlike Fleming and Netrebko, Germava sang on floats, not center stage.

Opera stars have never been typical sporting event singers, since opera is not outdoor event music or music mainstream audiences want to hear. However, while this year may seem to be a renaissance for opera singers, Domingo and many other opera singers have already performed at these types of sporting events.

For example, Domingo has attended every World Cup since 1970 except 1978. In 1982, the tenor sang the theme song in Spain, "El Mundial," and in 1990, he joined Jose Carreras and Luciano Pavarotti in Rome for one of the most historic concerts ever. Domingo returned in 1994 in Los Angeles to perform again with the three tenors. In 1998, he performed at the Champs de Mars and Eiffel Tower, and in 2002, he performed at Japan's Yokohama Arena. In 2006, he performed with Netrebko and Rolando Villazon in Germany right before the finale. Domingo was also present in 2010 when Spain won the World Cup, but he did not perform. However, he was an active presence in the media during the final game.

Pavarotti also had his fair share of performances at sporting events. Other than his performances with the three tenors in 1990 and 1994, the Italian tenor performed at the Winter Olympics in Turin, Italy -- his last public performance.

In 2012, German tenor Jonas Kaufmann showed up to the finals of the Champions League, where he performed a new version of the UEFA Champions League theme. The version was written for the event by Matt Clifford, and Kaufmann was accompanied by violinist David Garrett. While it was lip-synched due to the tenor's medical condition, it was significant for his career, as it also brought him a number of new followers.

Il Divo is considered an operatic group; the classical crossover group also performed at the World Cup in 2006. The group sang the official anthem and was accompanied by Toni Braxton.

Domingo's upcoming concert is to take place two days before the final, and it promises to have a mix of classical and Brazilian music. The tenor will also be joined by Puerto Rican soprano Ana Maria Martinez and pianist Lang Lang. While opera continues to struggle in the world, the frequent appearance at these sporting events is likely to garner interest and could be an answer to the decline in audiences.