[2] Partnering Leonardo Lavalle, Năstase was a winner in the boys' doubles event at the 1984 US Open.

It was his second Grand Slam final, having finished runner-up to Mark Kratzmann and Simon Youl in the 1983 Wimbledon Championships, with Olli Rahnasto.

With Andrei Dîrzu, he took part in Romania's doubles rubber against West Germany in their World Group Relegation Play-off.

[5] It was in the 1989 Wimbledon Championships, where he and Lan Bale lost in the opening round to Javier Frana and his former junior partner Leonardo Lavalle.

[5] He was a semi-finalist with Borja Uribe at Florence in 1989 but his best performance came in the 1990 Sanremo Open, which he and Goran Prpic won.