Anna-Lena Grönefeld (born 4 June 1985) is a German tennis player.
 She turned professional in April 2003.
Anna-Lena Grönefeld and Katarina Srebotnik were the defending champions, but Grönefeld didn't participate that year.
Anna-Lena Grönefeld and Shahar Pe'er were the defending champions, but Grönefeld chose not to participate.
 Pe'er instead played with Sania Mirza.
Jean-Julien Rojer (] ; born 25 August 1981) is a Dutch professional tennis player from Curaçao.
 His highest ATP singles ranking is 218th, which he achieved on 15 August 2005.
 A doubles specialist, his career-high in doubles is World No. 3, which he reached in November 2015.
 His former doubles partners include Eric Butorac and Aisam-ul-Haq Qureshi.
 He currently plays with Horia Tecău of Romania, with whom he won the men's double titles in the 2015 Wimbledon and 2017 US Open championships.
 With Anna-Lena Grönefeld, he also won the mixed doubles' title at the 2014 French Open.
 He attended UCLA where he competed for the UCLA Bruins men's tennis team.
Anna-Lena Grönefeld and Vania King were the defending champions, but Grönefeld decided not to participate this year.
Anna-Lena Grönefeld and Shahar Pe'er were the defending champions, but Grönefeld chose not to participate.
Manuel Orantes Corral (] ; born 6 February 1949) is a former tennis player who was active in the 1970s and 1980s.
 He won the US Open men's singles in 1975, beating defending champion Jimmy Connors in the final.
 Orantes reached a career-high singles ranking of World No. 2.
The 1978 U.S. Pro Tennis Championships was a men's tennis tournament played on outdoor green clay courts (Har-Tru) at the Longwood Cricket Club in Boston, USA.
 The event was part of the 1978 Grand Prix circuit.
 It was the 51st edition of the tournament and was held from August 21 through August 28, 1978.
 Despite pressure to switch to a hard court surface from the Association of Tennis Professionals (ATP) and some leading players, in line with the surface change made that year by the US Open which directly followed the Boston event, the tournament organization elected to remain a clay court tournament in 1978.
 Several top players including Björn Borg, Guillermo Vilas and Jimmy Connors elected not to play the tournament.
 Fourth-seeded and defending champion Manuel Orantes won the singles title and the accompanying $32,000 first-prize money.
 The final was delayed until Tuesday, August 29 due to rain.
The 1973 Louisville Open, also known as the First National Tennis Classic, was a men's tennis tournament played on outdoor clay courts at the Louisville Tennis Center in Louisville, Kentucky, USA.
 It was the fourth edition of the tournament and was held from 30 July through 5 August 1973.
 The tournament was part of the Grand Prix tennis circuit and categorized in Group A.
 The singles final was won by fourth-seeded Manuel Orantes who earned 80 Grand Prix points.
Kristina Barrois and Anna-Lena Grönefeld were the defending champions, but Grönefeld decided not to participate.
 Barrois partnered up with Yvonne Meusburger, but lost in the final to Kiki Bertens and Anne Keothavong.

Question: Are Manuel Orantes and Anna-Lena Grönefeld both tennis players?
Answer: yes