Chile crushed Nigeria 4-0 in the Under-20 World Cup on Sunday to set up a semi-final clash against holders Argentina, who defeated Mexico 1-0.
All four of Chile's goals came in extra-time, with Mauricio Isla on target twice after the game had finished goalless in regular time.
Nigeria's Ezekiel Bala had headed against the bar just before the break but the Chileans had the better chances in the second half in Montreal.
Six minutes into extra-time, Chile took the lead when Hans Martinez crossed to Jaime Grondona to head home.
Both sides were feeling the pace but Isla struck from the penalty spot a minute before the end of the first period and then he scored again three minutes after the restart.
Mathias Vidangossy completed the extra-time rout to book the Chileans a place in the last four.
Argentina had to fight hard in Ottawa against an excellent Mexico side who created several chances with Carlos Vela hitting the post on the half hour.
But Maximiliano Moralez grabbed the winner for Argentina on the stroke of half-time with a drive which deflected in off Julio Cesar Dominguez.
Argentina will face Chile on Thursday while Wednesday's semi-final features Austria against the Czech Republic. The final will be played on July 22 in Toronto.