Gertler was a great admirer of Béla Bartók. He recorded the complete violin works of the composer for the Supraphon label, including his two concertos, that was awarded Grand Prix du Disque in Paris (1967). He is considered one of the best players of Bartók's music. His recording of the "44 duos for violins", with Josef Suk, is considered one of the best versions available. Bartók and Gertler met first in connection with the transcribing of the "Sonatina for violin" and piano presumably in 1926, learning at first hand the composer's performance intentions for his own music. Bartók and Gertler gave concerts together, first at Papa (Hungary) in 1937, after it in Antwerp and Brussels in 1938.