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. It was founded in 1976 when it replaced the ILTF Satellite Circuit as the second tier of tennis. 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 PIF ATP Rankings are the merit-based method used by the Association of Tennis Professionals (ATP) for determining the qualification for entry as well as the seeding of players in all singles and doubles tournaments. The first rankings for singles were published on 23 August 1973 while the doubles players were ranked for the first time on 1 March 1976. Ranking points are awarded according to the stage of tournament reached, and the prestige of the tournament, with the four Grand Slam tournaments awarding the most points. The rankings are updated every Monday, and points are dropped 52 weeks after being awarded. Jannik Sinner is the current men's singles world No. 1.
The Lexington Challenger is a professional tennis tournament played on outdoor hardcourts. It is currently part of the ATP Challenger Tour and the ITF Women's World Tennis Tour, and has been held annually at the Hilary J. Boone Tennis Complex in Lexington, Kentucky, since 1995 for men and since 1997 for women. It is presented by Meridian Wealth Management.
The ATP Challenger Tour is the secondary professional tennis circuit organized by the ATP. The 2009 ATP Challenger Tour calendar comprised 20 top tier Tretorn SERIE+ tournaments, and 142 regular series tournaments, with prize money ranging from $25,000 up to $150,000.
The Maccabi Men's Challenger was a professional tennis tournament played on outdoor hard courts. It was part of the ATP Challenger Tour. It was held at the Maccabi Tennis Club in Melbourne, Australia, in 2009.
The BMW Ljubljana Open is a professional tennis tournament played on outdoor clay courts. It is currently part of the WTA 125 series of the WTA Tour. In the past, the Association of Tennis Professionals (ATP) organized an ATP Challenger which was last held in 2011. The tournament was first held in 1990 in Domžale, Slovenia, before moving to Ljubljana from 2002.
The São Paulo Challenger de Tênis was a professional tennis tournament played on outdoor clay courts. It was part of the Association of Tennis Professionals (ATP) Challenger Tour. The 2013 event was the first version of the tournament, which also featured a women's competition of the 2013 ITF Women's Circuit. It was sponsored by Braskem.
Kamil Majchrzak is a Polish professional tennis player. He has a career high ATP singles ranking of World No. 75 achieved on 28 February 2022 and a career high ATP doubles ranking of World No. 241 achieved on 8 August 2016.
Marc David Polmans is a South African-born Australian professional tennis player. Polmans has a career high ATP singles ranking of World No. 116 achieved on 12 October 2020. He also has a career high ATP doubles ranking of World No. 68 achieved on 16 October 2017. He won the 2015 Australian Open boys' doubles title with fellow Australian Jake Delaney, defeating Hubert Hurkacz and Alex Molčan in the final. He reached the semifinal of the 2017 Australian Open doubles with Andrew Whittington.
Hong Seong-chan is a South Korean tennis player. Hong has a career high ATP singles ranking of world No. 141 achieved on 9 September 2024 and a doubles ranking of No. 359 achieved on 16 January 2023. He is the current Korean No. 1 singles player.
Zhang Zhizhen is a Chinese professional tennis player. He reached a career-high ATP singles ranking of world No. 31 in July 2024 and a doubles ranking of No. 47 in July 2024. As of July 2023, he became the highest-ever ranked Chinese male tennis player. He is the current No. 1 Chinese player. He has won three singles and two doubles titles on the ATP Challenger, and two singles and two doubles titles on the ITF Futures Tour. He won a silver medal in mixed doubles alongside Wang Xinyu at the 2024 Summer Olympics.
The Zhuhai Open is a professional tennis tournament played on hardcourts. It is currently part of the ATP Challenger Tour and the ITF Women's Circuit, and is held in Zhuhai, China, since 2015.
The Jinan Open is a professional tennis tournament played on outdoor hardcourts. It is currently part of the ATP Challenger Tour and the ITF Women's World Tennis Tour. The tournament is held annually in Jinan, China since 2017.
The 2017 International Challenger Zhangjiagang was a professional tennis tournament played on hard courts. It was the first edition of the tournament which was part of the 2017 ATP Challenger Tour. It took place in Zhangjiagang, China between 5 and 10 September 2017.
The 2018 International Challenger Zhangjiagang was a professional tennis tournament played on hard courts. It was the second edition of the tournament which was part of the 2018 ATP Challenger Tour. It took place in Zhangjiagang, China between 3 and 9 September 2018.
The 2019 International Challenger Zhangjiagang was a professional tennis tournament played on hard courts. It was the third edition of the tournament which was part of the 2019 ATP Challenger Tour. It took place in Zhangjiagang, China between 18 and 24 March 2019.
Harold Mayot is a French professional tennis player. He has a career high ATP singles ranking of world No. 103 achieved on 14 October 2024. He also has a career high ATP doubles ranking of world No. 255 achieved on 16 September 2024.
Mark Lajal is an Estonian tennis player. He has a career high ATP singles ranking of world No. 191, achieved on 20 November 2023. He also has a career high ATP doubles ranking of No. 710, achieved on 9 September 2024. He is currently the No. 1 Estonian player.
The 2023 International Challenger Zhangjiagang was a professional tennis tournament played on hard courts. It was the fourth edition of the tournament which was part of the 2023 ATP Challenger Tour. It took place in Zhangjiagang, China between 28 August and 3 September 2023.
The 2024 International Challenger Zhangjiagang was a professional tennis tournament played on hard courts. It was the fifth edition of the tournament which was part of the 2024 ATP Challenger Tour. It took place in Zhangjiagang, China between 26 August and 1 September 2024.
2024 International Challenger Zhangjiagang 
