Although the Taeguk Warriors' place in the quarter-finals was confirmed with a match to spare by Australia's 4-0 win over Oman, Stielike wasn't satisfied with his side's performance in a 1-0 win over Kuwait 1-0 in Canberra on Tuesday night.

Nam Tae-hee scored the 36th-minute winner when he got in front of his marker to head Cha Du-ri's precise right-wing cross past goalkeeper Hameed Youssef and into the net.

While the world no. 69 side appeared to shake off its first-game nerves, showing some fire in attack, a clearly disappointed Stielike conceded the Koreans were lucky to leave the match with maximum.

It was obvious they were no longer group favourites, he said.

"With football like this, you cannot win the tournament," the German said. "With a performance like today, you cannot go far in this tournament."

Kuwait defended well in the first half, leaving the Koreans wandering and pacing as it searched for a goal in front of 8795 fans at Canberra Stadium.

But despite several clear opportunities in the second half, Korea Republic could not double their lead.

Stielike blamed pressure on the players for "easy mistakes" such as giving away the ball with loose passes.

"What I have to say is sad for my side (but) in a lot of phases, Kuwait was the better team - better handling of the ball, more moves, more passes," he said. "The result I consider, very, very lucky."

Korea Republic has four days until it faces Australia in its final Group A match, and Stielike is not confident his star-studded squad can trump the host.

"Against Australia, if we play the same way, (we'll have) no chance," the coach said.

His main concern is his depleted squad, with midfielder Lee Chung-Yong forced home after being ruled out for at least three weeks with a leg fracture.

Bayer Leverkusen star Son Heung-min was missing from the starting line-up suffering a fever, while Kim Chang-soo was also omitted after sustaining injuries in Saturday's 1-0 win over Oman.

"Our main objective now is the recuperation of the players," Stielike said.

"We'll have to see the next days what players will be 100 per cent (fit) to attack the game against Australia."

Kuwait faces Oman on Saturday, with a win labelled crucial by coach Nabil Maaloul.

Maaloul said injuries had plagued his side as well and he looked forward to the return of some of his "dangerous" players.

"The loss is OK. The players were not ready. Too many were injured."