question: Are Barbara Jordan and Nikola Pilić both former professional tennis players?
answer: yes
context: Title: Challenge of Champions
  Passage: 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.
  Title: Nikola Pilić
  Passage: Nikola "Niki" Pilić (born 27 August 1939) is a retired Croatian professional tennis player who competed for SFR Yugoslavia.
  Title: Barbara Jordan (tennis)
  Passage: 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.
  Title: Athletic DNA
  Passage: 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.
  Title: Jack Kramer
  Passage: 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.
citations: Nikola Pilić Barbara Jordan (tennis)