Thomas Muller's bid for the World Cup's Golden Boot continues after scoring his fourth goal of the tournament to seal Germany's place as Group G winners at the expense of the USA.
But the Americans are also through to the last 16 after Portugal lost out on goal difference, despite their narrow victory over Ghana.
Muller, who is now level with Neymar and Lionel Messi as the World Cup's top goalscorer so far, struck after the interval in a rain-soaked Recife following a finely-balanced first half.
Two months worth of rain fell on the city overnight but the Arena Pernambuco had withstood the brunt of it, as both sides took to the field needing only a draw to confirm their place in the second round.
But Germany certainly had no thoughts of going on the defensive as Muller – who notched a hat-trick against Portugal in the opener – flashed an ambitious volley wide in the first 60 seconds.
Joachim Low's side continued the assault, Jerome Boateng in particular finding joy down the right-hand side as a number of teasing crosses flashed across Everton keeper Tim Howard's goal.
After weathering that initial storm the USA nearly found the net in a rare foray upfield through Graham Zusi, who rasped a long-range shot inches over Manuel Neuer's crossbar.
But the Germans continued to look slick in possession and with 35 minutes gone Arsenal's Mesut Ozil forced a save from Howard, before the all-action Zusi thwarted an on-rushing Muller in the penalty area.
Nonetheless the first half yielded few clear-cut chances and much of that was down to the Americans' resolute defending, which continued after the break.
Only the presence of Omar Gonzalez put off Ozil from planting a header past Howard and the German threat would only grow with Miroslav Klose, who equalled the Brazilian Ronaldo's World Cup record of 15 goals in the draw with Ghana, on the pitch.
He had replaced Podolski at half time but his first chance went begging, heading Bastian Schweinsteiger's pin-perfect cross wide in acres of space.
It was instead left to Germany's younger marksman Muller to break the deadlock after the 24-year-old curled home the rebound from Per Mertesacker's initial header in the 55th minute.
Howard had parried straight into Muller's path yet his error had no immediate consequences for the USA, as Portugal and Ghana were locked at 1-1 with 30 minutes left to play.
Germany looked the more likely to add to their goal tally as substitute Mario Gotze and Ozil combining up front to great effect without finding the killer touch.
But Klinsmann's team, having faded after a bright first half, nearly sprang a surprise in injury time after fine defending stopped a goal-bound Alejandro Bedoya shot, before Clint Dempsey nodded inches over.
USA 1
Muller 55
Germany 0
Referee: Ravshan Irmatov (Uzbekistan)
Attendance: 42, 279
USA: (4-2-3-1): Howard, Gonzalez, Bradley, Besler, Beasley, Dempsey, Jones, Davis (Bedoya, 56), Beckerman, Zusi (Yedlin, 84), Johnson
Subs not used: Guzan, Yedlin, Diskerud, Brooks, Altidore, Johannsson, Wondolowski, Green, Cameron, Chandler, Rimando
Germany: (4-3-3): Neuer, Howedes, Hummels, Schweinsteiger (Gotze, 76), Ozil (Schurrle, 89), Podolski (Klose, 46), Muller, Lahm, Mertesacker, Kroos, Boateng
Subs not used: Zieler, Grosskreutz, Ginter, Khedira, Draxler, Durm, Mustafi, Weidenfeller, Kramer
