The ATP Challenger Tour, known until the end of 2008 as the ATP Challenger Series, is a series of international men's professional tennis tournaments. The Challenger Tour events are the second-highest tier of tennis competition, behind the ATP Tour. The ITF World Tennis Tour tournaments are on the entry-level of international professional tennis competition. The ATP Challenger Tour is administered by the Association of Tennis Professionals. Players who succeed on the ATP Challenger Tour earn sufficient ranking points to become eligible for main draw or qualifying draw entry at ATP Tour tournaments. Players on the Challenger Tour are usually young players looking to advance their careers, those who fail to qualify for ATP events, or former ATP players looking to get back into the big tour.
The ATP Salzburg Indoors is a professional tennis tournament played on indoor hard courts. It is currently part of the Tretorn SERIE+ of Association of Tennis Professionals (ATP) Challenger Tour. It has been held annually in Salzburg, Austria since 2009.
The 2011 ATP World Tour was the elite men's professional tennis circuit organized by the Association of Tennis Professionals (ATP) for the 2011 season. It was the 42nd edition of the tour and the calendar comprised the Grand Slam tournaments, supervised by the International Tennis Federation (ITF), the ATP World Tour Masters 1000, the ATP World Tour 500 series, the ATP World Tour 250 series, the ATP World Team Championship, the Davis Cup, and the ATP World Tour Finals. Also included in the 2011 calendar is the Hopman Cup, which does not distribute ranking points, and is organized by the ITF.
The 2010 ATP Salzburg Indoors was a professional tennis tournament played on indoor hard courts. It was the second edition of the tournament which is part of the 2010 ATP Challenger Tour and the Tretorn SERIE+ series. It took place in Salzburg, Austria between 15 and 21 November 2010.
Dušan Lajović is a Serbian professional tennis player. Lajović has won two singles and two doubles titles on the ATP Tour. On 29 April 2019, Lajović reached his career-high singles ranking of world No. 23. On 21 September 2020, he peaked at No. 82 in the doubles rankings.
The 2011 ATP Salzburg Indoors was a professional tennis tournament played on hard courts. It was the third edition of the tournament which is part of the Tretorn SERIE+ of the 2011 ATP Challenger Tour. It took place in Salzburg, Austria between 14 and 20 November 2011.
Dominic Thiem is an Austrian professional tennis player. He has been ranked as high as world No. 3 in singles by the Association of Tennis Professionals, which he first achieved in March 2020. Thiem has won 17 ATP Tour singles titles, including a Grand Slam title at the 2020 US Open where he came back from two sets down to defeat Alexander Zverev in the final. With the win, Thiem became the first male player born in the 1990s to claim a major singles title, as well as the first Austrian to win the US Open singles title. He had previously reached three other major finals, finishing runner-up at the 2018 and 2019 French Opens to Rafael Nadal, and at the 2020 Australian Open to Novak Djokovic. Thiem was also runner-up at the 2019 and 2020 ATP Finals, where he lost to Stefanos Tsitsipas and Daniil Medvedev, respectively.
Federico Gaio is an Italian professional tennis player. He competes mainly on the ATP Challenger Tour and on the ITF circuit. He has won four Challenger titles and nine ITF futures singles titles. He reached his career high ATP singles ranking of World No. 124 in February 2020. In doubles, he has won three Challenger and four ITF futures doubles titles. He reached a career high in doubles of World No. 165 on 9 March 2020 after his maiden ATP doubles final at the 2020 Rio Open partnering Salvatore Caruso.
Kaichi Uchida is a Japanese professional tennis player.
The Columbus Challenger is a professional tennis tournament played on hard courts. It is currently part of the ATP Challenger Tour and WTA 125K series. The ATP event is held annually in Columbus, Ohio, U.S.A, as it has been since 2015, the tournament's start. The women's edition started in 2021.
Federico Coria is an Argentine tennis player. He has a career-high ATP singles ranking of No. 49 achieved on 13 February 2023. He also has a career-high doubles ranking of No. 238, achieved on 22 November 2021. Coria has won one ATP Challenger doubles title at the 2016 Campeonato Internacional de Tênis de Campinas and two ATP Challenger singles titles at the 2019 Savannah Challenger and the 2021 Czech Open.
Sebastian Ofner is an Austrian professional tennis player. He has a career high ATP singles ranking of World No. 81 achieved on 12 June 2023. He is currently the No. 1 Austrian player.
Jurij Rodionov is an Austrian professional tennis player. He has a career high ATP singles ranking of World No. 114 achieved on 12 June 2023. He also has a career high doubles ranking of World No. 268 achieved on 15 July 2019.
Nathaniel Lammons is an American professional tennis player who specializes in doubles. He has been ranked by the Association of Tennis Professionals (ATP) as high as world No. 30 in doubles, which he achieved on 8 May 2023. Lammons also attained a career-high singles ranking of world No. 591 in January 2019.
The 2021 ATP Tour was the global elite men's professional tennis circuit organised by the Association of Tennis Professionals (ATP) for the 2021 tennis season. The 2021 ATP Tour calendar comprised the Grand Slam tournaments, the ATP Finals, the ATP Tour Masters 1000, the ATP Cup, the ATP Tour 500 series and the ATP Tour 250 series. Also included in the 2021 calendar were the Davis Cup, the Summer Olympics in Tokyo, Next Gen ATP Finals, Laver Cup, none of which distributed ranking points.
Holger Vitus Nødskov Rune is a Danish professional tennis player. He has been ranked as high as world No. 6 in men's singles by the Association of Tennis Professionals (ATP), making him the highest-ranked Danish player in the ATP rankings.
The Emilia-Romagna Open is a professional tennis tournament played on clay courts. It is currently part of the WTA Tour for women and minor league ATP Challenger Tour for men. It is held annually in Montechiarugolo, Parma, Italy since 2021 and 2019.
The 2021 ATP Salzburg Open was a professional tennis tournament played on outdoor clay courts. It was the first edition of the tournament which was part of the 2021 ATP Challenger Tour. It took place in Anif (Salzburg), Austria between 5 and 11 July 2021.
The NÖ Open is a professional tennis tournament played on clay courts. It is currently part of the ATP Challenger Tour. It is held annually in Tulln an der Donau, Austria since 2021.
The 2022 Salzburg Open was a professional tennis tournament played on outdoor clay courts. It was the second edition of the tournament which was part of the 2022 ATP Challenger Tour. It took place in Anif (Salzburg), Austria between 4 and 10 July 2022.
2021 ATP Salzburg Open 
