Pellegrini was capped once by the Chile national team, starting in a 1–1 friendly draw away to Brazil on 7 May 1986. He retired as a player a year later, in February 1987, after a match against Trasandino, with his reason for retiring being the following: "We were playing in the Copa Chile against Trasandino. Our goalkeeper parried the shot of a rival player, I jumped to clear the ball, and behind me came a 17-year-old boy who jumped half a metre above me, and scored. That day I decided I couldn't keep going". That boy was Iván Zamorano, on loan from Cobresal, who was the "Pichichi" of La Liga in 1995 with Real Madrid. Pellegrini confessed: "If I had known where that boy would get, I would not have retired. I would have kept playing two more years."