Question: Who appeared in the Olympics first, Piet Norval or Emilio Sánchez?

Passages:
Tomás Carbonell and Donald Johnson were the defending champions, but did not participate together this year.  Carbonell partnered Juan Balcells, losing in the first round.  Johnson partnered Piet Norval and successfully defended his title. Pieter ("Piet") Norval (born 7 April 1970) is a former tennis player from South Africa, who turned professional in 1988.  The right-hander represented his native country in the doubles competition at the 1992 Summer Olympics in Barcelona, where he partnered Wayne Ferreira.  The pair won the silver medal, after losing the final to Boris Becker and Michael Stich from Germany.  Norval reached his highest singles ATP-ranking on 19 June 1989, when he became the no. 125 of the world. Piet Norval and Kevin Ullyett were the defending champions, but did not participate this year. Mike Bauer and Piet Norval were the defending champions, but did not participate this year. Emilio Sánchez and Slobodan Živojinović were the defending champions, but Sánchez did not participate this year.  Živojinović partnered Boris Becker, withdrawing prior to their semifinals match. Emilio Ángel Sánchez Vicario (born 29 May 1965) is a former professional tennis player from Spain.  He won three Grand Slam doubles titles and the men's doubles silver medal at the 1988 Olympic Games.  He is the brother of multiple Grand Slam winner Arantxa.  Sanchez since retiring captained his nation to Davis Cup success in 2008.  In 2012 Sanchez was a tournament director for two wheelchair tennis events. Lucas Arnold and Tomás Carbonell were the defending champions, but did not participate together this year.  Arnold partnered Martín García, losing in the first round.  Carbonell partnered Piet Norval, losing in the first round. Arantxa Sánchez Vicario and Todd Woodbridge were the defending champions but they competed with different partners that year, Sánchez Vicario with Emilio Sánchez and Woodbridge with Helena Suková. Bent-Ove Pedersen (born 11 July 1967 in Oslo) is a former tennis player from Norway, who turned professional in 1992.  He spent several years playing tennis at Berkeley in California.  The right-hander represented his native country in the doubles competition at the 1992 Summer Olympics in Barcelona, where he partnered Christian Ruud.  The pair was defeated in the first round by South Africa's eventual runners-up Wayne Ferreira and Piet Norval.  Pedersen reached his highest singles ATP-ranking on 13 September 1993, when he became the number 366 of the world.  He was in quarterfinal in US Open doubles, 1991, partnering Matt Lucena from the US.  He became the number 78 on the doubles ranking 30.  August 1993. David Adams and Marius Barnard were the defending champions but they competed with different partners that year, Adams with Olivier Delaître and Barnard with Piet Norval.

Supporting sentences:
 The right-hander represented his native country in the doubles competition at the 1992 Summer Olympics in Barcelona, where he partnered Wayne Ferreira.  He won three Grand Slam doubles titles and the men's doubles silver medal at the 1988 Olympic Games.  Sanchez since retiring captained his nation to Davis Cup success in 2008.  In 2012 Sanchez was a tournament director for two wheelchair tennis events.