Germany stunned the Argentinians as Thomas Mueller headed past Romero in the 3rd minute. Thomas Mueller incidentally scored his fourth goal of the tournament.
The Germans were swarming ahead and marching ahead for their second goal. Youngsters Ozil and Mueller were combining well and keeping the Argentinian defense on their toes. The Argentinians looked like they were panicking and were giving away possession rather sloppily.
Around the 22nd minute mark Messi put a delightful ball for Tevez who made an ambitious run to reach for the ball, but eventually the German keeper collected the ball before he could reach. The Germans should have doubled their lead in the 24thm minute as Klose playing his 100th cap missed a golden opportunity, after Mueller cut a ball for him from the right side.
Messi was trying hard to outplay the German defense, playing those depth touches but the Germans defense was standing tall and not letting any space for Messi and his striking partners.
Around half-hour mark, Messi got a free-kick in a decent position, about 28 metres away from the German goal but his free-kick was way over the bar.
Higuain made a good movement in the penalty box around the 35th minute mark and hit a left-footed shot but his shot was denied by the goalkeeper. Moments later Argentina managed to find the back of the net, but the goal was ruled out as the Argentina player was clearly offside.
Podolski around the 39th minute, hit a powerful left-footed drive but his shot was wide off the mark.
Around the 44th minute, Lahm made a brilliant run in the right flank and cut the ball for Mueller, who managed to pull off a shot but his effort was deflected for a corner. Messi finally found an open space to make his shot towards the end of the first half, but he ballooned the ball way over the bar.
So as the players went for break, Argentinians were 1 nil down.
Argentina started off positively as Messi, Tevez combined well to break forward and kept the German defense on red-alert. Angel Di Maria hit a flashing drive with his left foot which was just off the German goal in the 49th minute.
Just few minutes later, Di Maria again was in the thick of action as he put one dangerous ball in the German penalty box from the right flank for Tevez to try out a volley, but Tevez's volley was blocked by the German defender.
Germans came close in the 58th minute, for Klose who was unmarked and clear off the defenders, but Romero bravely fisted the ball out of danger before Klose could reach.
Around the hour mark the game was looking open with both teams getting the ball from end to end, bringing out constant threat for defenders for both side.
Tevez came up with a long-range shot in the 62nd minute, but his effort was denied by the keeper. Minutes later, the Argentinians again marched forward, with Messi cutting the ball for Higuain who hit a shot but his effort was again denied by Manuel Neuer.
Neuer was really kept busy with Di Maria once again coming up with his left-footed effort, but his shot was comfortably caught by the goalkeeper.
However after Argentina soaking up with a lot a possession and chances, it was Germany though with Klose who found the goal as the Germans lead the game by 2-0, in the 68th minute. Klose in the process overtook Pele with 13 goals in World Cup competition, his 51st goal playing for Germany.
Germany then stunned the Argentinians scoring their third goal in the 74th minute after Schweinsteiger made a terrific run beating the defenders to cut it out for Arne Friedrich who got the final tap as the Argentinians more in misery. The Argentina defenders were clearly struggling at that moment every time the Germans marched forward with the ball. Schweinsteiger and Klose was easily gliding past the defense at that period of play, as the Argentinians looked totally out of the match.
Toni Kroos coming in as substitute hit a thunderous shot, in the 80th minute but his effort was denied by Romero.
Klose added another in the 89th minute, Mesut Ozil's measured an excellent cross with a minute remaining to round off a memorable German win.
Germany will now face Spain who won a hard fought against Paraguay in their next match in the Semi-finals.