Thomas Mueller, Lukas Podolski and Cacau also scored as the Germans went atop Group D.
Just hours after Ghana set the pace in Group D with their 1-0 win over Serbia, Germany and Australia looked to keep up with the Black Stars as they kicked off in Durban.
Germany coach Joachim Loew made one change to the lineup that featured in last week's 3-1 victory over Bosnia and Herzegovina: on the right flank, Thomas Mueller replaced Piotr Trochowski. Miroslav Klose, who has taken heavy criticism in recent weeks, got the nod as Loew's lone striker, pipping the in-form Cacau.
For Australia, Pim Verbeek made somewhat of a surprse selection in the striker position. With Harry Kewell unfit, it at first seemed that Joshua Kennedy was a shoe-in for the role up top. However, Verbeek opted to use Everton midfielder Richard Garcia in attack, with Brett Emerton, Tim Cahill , and Jason Culina as support.
Australia took no time to get started, and should have gone a goal ahead within three minutes. Following a corner, Cahill's header was blocked by Germany captain Philipp Lahm, and Garcia's follow-up was also deflected away from goal.
It wasn't long before Germany found their feet. After Mesut Ozil nearly played Lukas Podolski through on goal, the young playmaker found Klose breaking away from Vincenzo Grella. The Bayern Munich striker raced to the edge of the penalty area, but Mark Schwarzer made a good save to deny him.
Moments later, Ozil slipped a clever ball through to Mueller, who pulled back for Podolski. The Koeln man fired with his first touch, blasting in off Schwarzer's hand to put the Germans ahead.
After a spell during which the Germans held the ball well but had trouble timing their runs, the Aussies nearly drew level. Emerton's cross found Culina's head at the back post, but the Gold Coast United man nodded over the bar. Moments later, Wilkshire found Emerton with a fine through ball before Garcia cleverly created space for himself to shoot. The striker's last touch was lacking, however, and the ball flew well over the bar.
The Germans would soon punish their opponents for poor finishing. The catalyst, Ozil, first played a fine ball that resulted in Klose missing a wide-open shot from the centre of the penalty area. Then, Lahm sent an inch-perfect cross to Klose that fooled Schwarzer. The goalkeeper raced off his line, but failed to collect the ball as Klose emphatically headed home his 11th World Cup goal.
With the score reading 2-0, Germany were well in control, but continued to pressure the Australian goal. Their use of width stretched the Socceroos' defence, and their variety of attacking options kept the Aussies on their heels. Ozil failed to convert on a pair of one-on-one opportunities with Schwarzer, and Sami Khedira nearly added a goal of his own after receiving another well-taken cross from Lahm.
Only in the dying moments of the first half did Australia manage to bring the ball back into their attacking third, but Garcia posed a very lonely figure in the penalty box.
The first half ended with Germany comfortably ahead as a dejected Australian side was left to figure out how to find their way back into the game.
After the break, Verbeek withdrew Grella in favor of the more attack-minded Brett Holman. Australia started well and had claims for a penalty after Garcia headed the ball off Per Mertesacker's arm. It would have been a harsh decision, but penalties have been awarded for less.
Within seven minutes, Holman nearly pulled a goal back for Australia. The substitute created space away from Friedrich and fired from 20 yards, but missed wide of the right post.
The Australians' momentum would soon run out, and their hopes of taking anything from the game were vanquished after 56 minutes, when Cahill was sent off for a poor foul on Bastian Schweinsteiger. The Everton midfielder tried to pull out of his challenge, but was late and connected with the German's ankle, which was enough to earn a straight red card.
Meanwhile, the Germans played for a third goal as Mueller, Khedira, Klose, and Podolski fired but could not quite beat Schwarzer.
Inside the final half hour, Verbeek swapped Garcia for Ukraine native Nikita Rukavytsa, but if anything, Australia could have used another defender. As the final quarter of the game approached, Podolski fed a through ball to Mueller, who wisely stopped his run to create space. The Bayern Munich attacker then struck a precise effort off the inside of the left post to make the score 3-0.
Even with a comfortable lead, Loew decided to keep attacking, and next substituted Cacau in place of Klose. With his first touch, the Stuttgart striker slotted in after Ozil slipped into a forward position and teed him up.
With a quarter hour left, Loew brought on striker Mario Gomez in place of Ozil, and the Germans' style of play switched to a strictly flank-based attack. Australia had their first bright spell since early in the first half, but as before, could not quite capitalize. Six minutes from full time, the Aussies had their first opportunity on goal since the third minute, but Rukavytsya was harried and fired weakly into goalkeeper Manuel Neuer's waiting arms.
With the result already decided, the match drew to a rather quiet close. Australia struggled to keep possession in their attacking half, and a comfortable Germany side played out the final minutes without throwing players forward as they previously had.
The result puts Germany atop Group D, ahead of Ghana on goal difference. After Serbia's loss earlier today, Australia still have a chance to advance to the knockout rounds, but have a mountain to climb.
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