Australia coach Holger Osieck was satisfied with the professional way his team dealt with India at the Asian Cup, but the Socceroos know they need to step up a gear against South Korea.

The Australians swept aside the gallant Indians 4-0 to get their tournament off to a decisive start late on Monday, with Everton attacking midfielder Tim Cahill scoring twice.

He got the opener in the 11th minute before former Liverpool man Harry Kewell made it 2-0 14 minutes later. Brett Holman added a third on the stroke of halftime before Cahill completed the demolition.

Despite the scoreline, Australia spurned several chances and Osieck knows it cannot afford any errors against the Koreans on Friday in a game that should determine who tops Group C.

"We scored three goals, which was encouraging, and to start with a 4-0 all in all is good and should give us confidence for the next games to come," said the German, who led Japan's Urawa Reds to AFC Champions League glory in 2007.

"There were a number of opportunities that we could've scored from but sometimes it's not always easy to finish them off.

"You never can force it. I think the boys themselves know what they have to do when we play our next game."

South Korea beat Bahrain 2-1 in its opener, with Koo Ja-cheol striking either side of halftime, as Cho Kwang-rae's team bids to end a 51-year continental title drought. Ranked 40th in the world to Australia's 26th, the Koreans are led by Manchester United star Park Ji-sung and fared better than the Socceroos at the South Africa World Cup, reaching the round of 16 before losing to Uruguay.