Klinsmann's side came through an epic last-16 game in Doha and must now recover in time to take on an Australia side that had two days more to recover.
The German legend said his players are "ready for a battle" as they look to book a semi-final place against either Jordan or Tajikistan.
"If you want to go through to the knockout phase of a big tournament you have to suffer," said Klinsmann on Thursday.
"You have to be ready to suffer, you have to deal with pain."
South Korea had to come back from the dead to see off Roberto Mancini's Saudis, scoring a 99th-minute equaliser to take the game into extra time.
Led by Son Heung-min, the Koreans started slowly but found their attacking spark and had several chances to win the game before the shootout.
They are looking to win the Asian Cup for the first time since 1960.
Klinsmann won the World Cup and European Championship as a player and is keen to share his tournament experience with his players.
"Now it gets down to the grinding phase," he said.
"Now it's the big stage, and I love this moment. I hope they enjoy that too."
Australia had a far more comfortable route to the quarter-finals, cruising past Indonesia 4-0 in the first game of the last 16.
Coach Graham Arnold said he had given his players a day off and they were "in good spirits" ahead of the game against the Koreans.
"They've got a strong squad but it's about what we do," he said.
"We know their strengths and we'll deal with them in the best way we can.
"It's about getting our game right and I truly believe that the most important thing for us is good football."
Arnold noted that Australia have conceded only one goal at the tournament to South Korea's seven.
He said the Socceroos intended to "be in their faces for 90 minutes".
"One of their strengths is their technique and we can take away the technical side of things," said the coach.
"The way of doing that is pressuring."