Are Barbara Jordan and Nikola Pilić both former professional tennis players?
yes
Barbara Jordan (tennis)
Barbara Jordan (born April 2, 1957) is a former professional female tennis player from the United States who won the 1979 Australian Open singles title.
Nikola Pilić
Nikola "Niki" Pilić (born 27 August 1939) is a retired Croatian professional tennis player who competed for SFR Yugoslavia.
1969 Stockholm Open – Singles
The 1969 Stockholm Open was a tennis tournament played on hard courts in Stockholm, Sweden.
 The tournament was held from November 1 through November 7, 1969.
 Nikola Pilić defeated Ilie Năstase in the final, 6–4, 4–6, 6–2. Boro Jovanović
Boro Jovanović (born 21 October 1939) is a former Yugoslav tennis player.
 Jovanović was runner-up in the 1962 Wimbledon doubles tournament with Nikola Pilić, and quarter-finalist in the 1968 Wimbledon doubles tournament.
 In singles, Jovanovic reached the final of the 1963 Italian Open and the quarterfinals of the 1968 French Open.
 In 1972, Boro Jovanović joined the World Championship Tennis Tour. Challenge of Champions
The "Challenge of Champions" was created to be one of the richest prize money tennis events in the world.
 Created by Leo E. Fenn III in 1985 as an Invitation Only Tennis Tournament which would feature daily matches which were the equivalent to the Finals of the US Open or Wimbledon.
 It was usually held before the Masters and invited only the top eight men's tennis players in the world according to their rankings on the ATP poll.
 In 1985, creator & founder 24-year-old Leo E. Fenn III partnered with 28-year-old Mark Myden to form a company called Special Events Productions.
 SEP produced the "Challenge of Champions" Tournament which became a major player in professional tennis.
 These two entrepreneurs became the youngest producers in history of professional tennis.
 Leo & Mark acquired major fortune 500 corporate sponsors such as AT&T, VISA, Cadillac, Fila Sportswear, DeBeers Diamonds as well as negotiated two days of live weekend television coverage on NBC.
 Their title sponsorship package sold to AT&T was the largest single vent sponsorship package in professional tennis that year.
 Leo negotiated with the brand new Thomas Mack Center Arena in Las Vegas to host the inaugural event.
 The event rights were eventually sold to Pro Serve and concluded following the 1989 Challenge. 1973 Wimbledon Championships – Men's Singles
Jan Kodeš defeated Alex Metreveli 6–1, 9–8, 6–3 in the final to win the Gentlemen's Singles title at the 1973 Wimbledon Championships.
 The final match included a tie-breaker played at 8–8 in the second set; the first ever Wimbledon singles final to include a tie-break.
 Eighty-one of the top players boycotted Wimbledon in 1973 (including reigning champion Stan Smith) to protest against the suspension of Nikola Pilić. Ana Jovanović
Ana Jovanović (Serbian Cyrillic: Ана Јовановић; born 28 December 1984) is a Serbian former professional tennis player.
 She was coached by Nikola Pilić. David Falk
David B. Falk (born 1950) is an American sports agent who primarily works with basketball players in the National Basketball Association.
 Falk began his career representing professional tennis players for Donald Dell's ProServ and is best known for representing sports icon Michael Jordan for the entirety of Jordan's career.
 Besides Jordan, Falk has represented more than 100 other NBA players, and is generally considered to be the most influential player agent the NBA has seen.
 During the peak years of Falk's career in the 1990s, he was often considered the second-most powerful person in the NBA behind Commissioner David Stern, and in 2000 he had at least one client on all but two NBA teams.
 He was listed among the "100 Most Powerful People in Sports" for 12 straight years from 1990 to 2001 by "The Sporting News", and was also named one of the Top 50 Marketers in the United States by Advertising Age in 1995. Athletic DNA
Athletic DNA (ADNA) is an American sports apparel company.
 Founded in Seattle in 2007, ADNA began by training young tennis athletes, which evolved into sponsoring Select Junior Tennis players, and then expanded to manufacturing clothing for youth and adult tennis players.
 ADNA has since spread to professional tennis, and currently sponsors players on the ATP Tour & WTA Tour. Jack Kramer
John Albert Kramer (August 1, 1921 – September 12, 2009) was an American tennis player of the 1940s and 1950s.
 A World No. 1 player for a number of years, and one of the most important people in the establishment of modern men's "Open"-era tennis, he was the leading promoter of professional tennis tours in the 1950s and 1960s.
 He was a relentless advocate for the establishment of Open Tennis between amateur and professional players.
 An International Tennis Federation (ITF) proposal to introduce Open tennis lost by five votes in 1960, but became a reality in 1968.
 In 1970, he created the Men's Grand Prix points system.
 In 1972, he helped found the Association of Tennis Professionals (ATP) with Donald Dell and Cliff Drysdale, and was the first Executive Director.
 He was unpaid at his request.
 In that role, he was the leader of an ATP boycott of Wimbledon in 1973, for the banning of Nikola Pilić from the tournament.