[citation needed] After finding some form following a difficult start, a serious knee injury sustained in a clash with compatriot Diego Maradona in January 1990 ended his season early,[1] while in his absence the team reached the final of the 1989–90 UEFA Cup.

Only three foreign players were allowed to play in each match, and the club filled Dertycia's vacant slot with Marius Lăcătuș (a year later La Viola signed another Argentine with similar attributes, Gabriel Batistuta, to lead the attack to great effect).

[2] Without prospect of another opportunity at Fiorentina, Dertycia first transferred to Spanish club Cádiz CF where he garnered a firm fanbase, being nicknamed Mister Proper due to the distinctive bald head he has worn since retirement.

[1] He moved to CD Tenerife in 1991 as a replacement for Rommel Fernández, being a useful offensive footballer for said Canary Islands club under compatriots Jorge Valdano, Diego Latorre, and Fernando Redondo.

[1] After appearing with the Argentine under-20 team at the 1983 FIFA World Youth Championship, scoring once to help his country reach the final,[4] In 1984, Dertycia received his first senior call-up under Carlos Bilardo, and debuted in a friendly match against Colombia the same year.