Delon was very cool on screen. Although, in critical terms, Melville’s Le Samourai is better respected, I enjoyed Tessari's Tony Arztena far more. (But 1970s Italian pulp is my cinematic equivalent of comfort food... )
BTW. my review of Le Samourai is here (ICYMI)
https://medium.com/framerated/le-samourai-1967-blu-ray-criterion-collection-dc6948ea052c