Due to his interest in Jazz, he started to be part of the “Santa Fe Jazz Ensemble Junior” where he had the possibility to train with different local and international professors. He attended a masterclass of harmony and improvisation given by the great trombonist Conrad Herwig in the framework of the international festival “Trombonanza”. He also received training in a clinic of harmony and improvisation provided by the trombonist Andy Hunter (USA) in the year 2008. Same year in which he began to be a permanent musician of “Santa Fe Jazz Ensemble” (professional Big Band from Santa Fe) and a group on which he had the chance to play along outstanding musicians from all over the world. He took private Jazz lessons with trumpet player Guillermo Calliero.

Faced with the need to expand his knowledge in the language of Jazz, harmony and improvisation, he started to take lessons with the trumpeter and composer Juan Cruz de Urquiza.

He participated in a harmony and improvisation clinic by the legendary Argentinian trumpet player, Roberto "Fats" Fernandez.

In 2012 he auditioned and got accepted into the Manuel de Falla Superior Conservatory of Music of the city of Buenos Aires. He began to form part of the Conservatory?s Big Band and in December 2012 participated in the International Jazz Festival of Buenos Aires next to the American drummer and composer John Hollenbeck.

Then he moved to Buenos Aires to continue his studies at the Manuel de Falla Conservatory, and to work professionally as a musician and in the same year he was chosen to be part of a Big Band that participated in the International Tango Festival of Buenos Aires.

He was also selected through an audition to become a trumpeter for the nonet of the Manuel de Falla Conservatory to play music by the American saxophonist Tim Berne, performing alongside the renowned artist at the International Jazz Festival of the city of Buenos Aires, where he reappeared the following year, in this case as lead trumpet of the Big Band of the Conservatory playing music of the Trombonist Ed Neumeister with the participation of the aforementioned artist as a soloist.

He received two scholarships from the National Arts Fund of Argentina to participate in the third composition and improvisation meeting, held in the city of Bariloche, Argentina and the fourth meeting of Composition and Improvisation held in the city of Buenos Aires, Argentina for which he was selected among the outstanding alumni.

Previously this same year, he received a scholarship to participate in the ensemble "Música Maestra" (“Master Music”), taught by Professor Juan Cruz de Urquiza. In 2016 he graduated from the Manuel de Falla Superior Conservatory as a „Superior Technician in Jazz with Trumpet orientation?. He is then selected to be part of a training course given by the American pianist Marilyn Crispell and attends a masterclass by the famous American jazz trumpeter Bobby Shew.

Up to 2017, he was a staff member of the EMC (School of Contemporary Music) Berklee International Network as Professor of Trumpet, jazz ensemble and musical notation.

He took a masterclass with the emblematic American pianist and educator Dr. Barry Harris and a masterclass with the trumpeter and composer Ralph Alessi. Also he participated in a Rhythm and Composition clinic by Guillermo Klein and in the same year he participated in a masterclass by the American pianist David Kikoski.

Since the end of 2017 he has created his own quartet with own music, an ambitious project that brings together renowned young musicians of the new generation of Argentine Jazz such as Sebastián de Urquiza on double bass, Nicolás Boccanera on piano and Matías Crouzeilles on drums. In 2018 he recorded his first album as a soloist and composer and received an Honorable Mention from the National Fund for the Arts in Unpublished Jazz category. He was also invited to participate in the International Jazz Festival of the City of Buenos Aires, Argentina.

Sebastián participated in the Tucumán (province of Argentina) International Jazz Festival. In July of the same year, his first record work entitled "Paisaje" (“Landscape”) released by the American label, Ears & Eyes Records and presented at the main Jazz clubs in the city of Buenos Aires, at La Usina del Arte, in Montevideo, Uruguay and in Santa Fe, Argentina. The same year he attended a Masterclass of the saxophonist Seamus Blake.

Three of his composition was included to the “Real Book Argentina” (The Argentinian Real Book).

Sebastián Greschuk has been chosen as revelation musician 2019 by “El Intruso” (a media from Argentina)