"I don't think Vietnam are weak at all," the German coach said at a press conference Monday.

At an earlier press conference last month he said South Korea needed to play strong teams instead of Vietnam, a view the country's media gleefully picked up.

He said Monday: "We will approach this game like an official one to see our progress and what we need to improve."

South Korea might meet Vietnam in tournaments like the 2024 Asian Cup or the 2026 World Cup qualifiers, and so the match is a preparation for the team for such scenarios, he said.

South Korea have played Vietnam six times, won five and lost one.

Currently, they are 26th in the FIFA rankings, 69 places above Vietnam.

They do not have many options for friendlies because European and South American teams are busy playing in the 2024 Euro and 2026 World Cup qualifiers.

Klinsmann said he plans to field a strong lineup and use all six substitutions.

"We must maintain continuity and consistency in the squad. The other important thing is to make time for those who rarely have the opportunity to play."

He left open the possibility of captain Son Heung-min and midfielder Hwang In-beom playing, as they have just returned from injury.

Vietnam head coach Philippe Troussier said Vietnam will play defensive football in this game to deal with the stars of South Korea.

"Vietnam will defend in 60 to 70% of the time. I told the players this is not a test or a challenge. This game is like a gift because the players get to encounter top footballers in the world," Troussier said.

Before this game, Vietnam suffered defeats against China and Uzbekistan, both 0-2. South Korea defeated Tunisia 4-0.

Klinsmann, 59, was a legendary German striker, scoring 47 goals in 108 matches for his country and winning the 1990 World Cup and Euro 1996.

His club career was also successful with spells at Stuttgart, Inter Milan, Tottenham and Bayern Munich, scoring 232 goals in 514 matches.

But his coaching career, in which he has managed the German and U.S. national teams and two German clubs, Bayern Munich and Hertha BSC has been considerably less successful.

Klinsmann signed a three-year contract with the Korean Football Federation to replace Paulo Bento in March 2023, and is tasked with qualification for South Korea's 11th consecutive World Cup in 2026.