|Born||16 February 1960
|Height||1.80 m (5 ft 11 in)|
|Highest ranking||No. 58 (28 Jan 1985)|
|Grand Slam Singles results|
|French Open||3R (1981)|
|US Open||1R (1985)|
|Highest ranking||No. 89 (7 Apr 1986)|
|Grand Slam Doubles results|
|French Open||1R (1981, 1982)|
In 1982 he was runner-up in the Buenos Aires Grand Prix tournament and made quarter-finals at Venice, Boston and Quito. He had an upset win over third seed Eliot Teltscher in Boston. At the French Open that year, Ganzabal defeated Júlio Góes in the opening round but was unable to overcome Mike Myburg in the second round, losing in five sets.
The Argentine didn't make an appearance on the 1984 Grand Prix season until July, as he had been ill with hepatitis. He finished the year well, making the quarter-finals in North Conway, semi-finals in Geneva and quarter-finals in Indianapolis. At these tournaments he secured two wins over top 20 player Tomáš Šmíd and also defeated world number 11 Henrik Sundström.
Ganzabal beat Russell Simpson in the opening round of the 1985 French Open, then lost to countryman José Luis Clerc. He was however unable to progress past the first round at the 1985 US Open, losing to Brian Teacher.
He took part in three Davis Cup ties for Argentina, all while they were in the World Group. In 1982 he played a doubles rubber with Guillermo Vilas, which they lost to the French pairing of Gilles Moretton and Yannick Noah. He other two matches were dead rubbers and he lost both, against Michael Westphal of West Germany and American player Gene Mayer.
Grand Prix career finals
Singles: 1 (0–1)
|Outcome||No.||Year||Tournament||Surface||Opponent in the final||Score in the final|
|Runner-up||1.||1982||Buenos Aires, Argentina||Clay||Guillermo Vilas||2–6, 4–6|
Doubles: 1 (1–0)
|Outcome||No.||Year||Tournament||Surface||Partner||Opponents in the final||Score in the final|
|Winner||1.||1985||Bari, Italy||Clay||Claudio Panatta|| Marcel Freeman
|No.||Year||Tournament||Surface||Partner||Opponents in the final||Score in the final|
|1.||1982||Bari, Italy||Clay||Gustavo Guerrero|| Luca Bottazzi