SYDNEY, Australia -- Taylor Fritz and Madison Keys put Team USA into the United Cup City Finals after posting straight-set wins over Germany on Day 5. 

Team USA will face Great Britain in Wednesday's City Finals. Team GB went 2-0 in Group D, tallying wins over Australia and Spain. The winner of the City Finals will advance to the United Cup Final Four, which begins on Friday in Sydney.

After defeating the Czech Republic 4-1 in their opening tie, the Americans came into the day needing just two points from Germany to ensure their spot at the top of the table in Group C.  

Fritz quickly gave the Americans a 1-0 lead with a 6-1, 6-4 win over Alexander Zverev 6-1, 6-4. In a dominant display on Ken Rosewall Arena, the 25-year-old raced out of the blocks, winning the first five games as he stepped inside the baseline to ruthlessly finish points. The World No.9 produced a strong serving performance, winning 96% (26/27) of points behind his first delivery.

Keys followed Fritz's lead with an efficient performance of her own, defeating Jule Niemeier 6-2, 6-3 to tally her second win of the season. 

In the first meeting on tour between the two powerful baseliners, Keys' effortless power and pinpoint serving proved too much for the 23-year-old German. A surprise quarterfinalist last summer at Wimbledon, Niemeier struggled with the rhythm on her serve throughout the match. She opened with three double faults in her opening game to give Keys the early break and the experienced American was off and running. 

Serving at 77%, Keys lost just six points behind her vaunted first serve and did not faced just one break point in the 71-minute match. Niemeier finished with seven double faults for the match. The German fought valiantly in the final games,  fighting off Keys in a seven-minute game to hold to 4-2 in the second set and then broke Keys on her only break point of the match. 

But Keys steadied herself and recovered, breaking Niemeier for a fourth time to lead 5-2 and coolly serving out the win.

"I think overall I played really solid," Keys said. "I just tried to make as many first serves as possible to make things as easy as a tennis match could be."

The tie concludes on Tuesday, as the U.S. looks to clinch the win and go 2-0 in Group C. America's No.1, Jessica Pegula will look to pocket her first win of the season, against Laura Siegemund. Frances Tiafoe will face Oscar Otte. 

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