Question: Natasha Zvereva and Fred McNair were both what?

Context paragraphs:
1997 Acura Classic – Doubles: Lindsay Davenport and Natasha Zvereva were the defending champions but they competed with different partners that year, Davenport with Chanda Rubin and Zvereva with Gigi Fernández.

2000 Toray Pan Pacific Open – Doubles: Lindsay Davenport and Natasha Zvereva were the defending champions, but Davenport did not compete this year.  Zvereva teamed up with Katarina Srebotnik and lost in quarterfinals to Lisa Raymond and Rennae Stubbs.

1996 Porsche Tennis Grand Prix – Doubles: Gigi Fernández and Natasha Zvereva were the defending champions but only Zvereva competed that year with Lisa Raymond.

1999 Wimbledon Championships – Women's Doubles: The 1999 Wimbledon Championships – Women's Doubles was the women's doubles event of the hundred-and-thirteenth edition of Wimbledon, the third Grand Slam of the year, the most prestigious tournament on grass courts, and the oldest tennis tournament in the world.  Martina Hingis and Jana Novotná were the defending champions but only Novotná competed that year with Natasha Zvereva.  Novotná and Zvereva lost in the semifinals to Mariaan de Swardt and Elena Tatarkova.

Natasha Zvereva: Natasha Zvereva, or Zverava, (born Natallya Maratawna Zverava; Belarusian: Наталля Маратаўна Зверава; 16 April 1971) is a former tennis player from Belarus.  Zvereva was the first major athlete in the Soviet Union to demand publicly that she should be able to keep her tournament earnings.  The team of Zvereva and Gigi Fernández won more women's doubles titles and Grand Slam women's doubles championships than any other team since that of Martina Navratilova and Pam Shriver.

1995 Ameritech Cup – Doubles: Gigi Fernández and Natasha Zvereva were the defending champions but only Zvereva competed that year with Lori McNeil.

1999 Porsche Tennis Grand Prix – Doubles: The 1999 Porsche Tennis Grand Prix – Doubles was the tennis doubles event at the 1999 Porsche Tennis Grand Prix, the twenty-second edition of the most prestigious tournament in Baden-Württemberg.  Lindsay Davenport and Natasha Zvereva were the defending champions, but they did not compete this year.  Davenport competed with Martina Hingis as the first seed, while Zvereva competed with Elena Tatarkova.  Davenport and Hingis withdrew in the quarterfinals due to Davenport having a wrist injury, whilst Tatarkova and Zvereva were knocked out in the first round.

Fred McNair: Frederick V. McNair IV (born July 22, 1950 in Washington, D.C.) is a former professional tennis player from the United States who reached the World No. 1 doubles ranking in 1976.  That year, he teamed up with Sherwood Stewart to capture the men's doubles titles at French Open, the German Open and the Masters.  McNair was also a mixed doubles runner-up at the French Open in 1981, partnering Betty Stöve.  In 1978, he was a member of the US team that won the Davis Cup.  In nine years on the professional tour, McNair won 16 doubles titles.  His career-high singles ranking was World No. 67.

1997 Toray Pan Pacific Open – Doubles: Gigi Fernández and Natasha Zvereva were the defending champions but they competed with different partners that year, Fernández with Martina Hingis and Zvereva with Lindsay Davenport.

1999 French Open – Women's Doubles: Martina Hingis and Jana Novotná were the defending champions, but they did not compete together this year.  Novotná instead partnered with Natasha Zvereva as the first seed, whereas Hingis partnered with Anna Kournikova as the second seed.  Novotná and Zvereva retired in their quarterfinal match against Lindsay Davenport and Mary Pierce, but Hingis and Kournikova reached the final where they lost to American sisters Serena and Venus Williams, 6–3, 6–7, 8–6.  This was the first Grand Slam for the Williams sisters and would be their first step towards completing a Career Golden Slam in doubles.

Supporting paragraphs: Natasha Zvereva Fred McNair
Answer: tennis player