Santiago Phelan has resigned as Argentina coach just days before the Pumas start their northern hemisphere tour.
Phelan, whose contract had been due to end in December, brought forward his decision to leave after Argentina finished bottom of the Rugby Championship for the second year in succession with six defeats.
The 39-year-old is expected to give a press conference on Tuesday to explain his decision.
Argentina will play November Test matches against England at Twickenham on November 9, Wales a week later at the Millennium Stadium and Italy in Rome on November 23.
A statement on the Union of Argentina Rugby's website said: "Santiago Phelan will not continue his role as head coach of Los Pumas after six years in office.
"During his career as Pumas coach, Santiago Phelan was in charge of 45 matches in which there were 13 wins, one draw and 31 defeats.
"His debut was on June 7, 2008 against Scotland, while his last game in charge was against Australia in the Rugby Championship in 2013."