PERTH, Australia — Dominika Cibulkova and Dominik Hrbaty won their singles matches over Germany on Thursday — aided by an injury to Nicolas Kiefer — to send Slovakia to the Hopman Cup final.

Cibulkova beat Sabine Lisicki 7-6 (3), 6-4 in the women's singles.

In the men's singles, Hrbaty was trailing 3-1 in the opening set when Kiefer turned his right ankle. Unable to continue, Kiefer, 31, had his ankle heavily taped and was taken off the court in a wheelchair, his availability for the Australian Open which begins Jan. 19 uncertain.

The win gave Slovakia an unbeatable 2-0 lead and a place in Friday's final.

In the other Group A match Thursday, the United States beat Australia 2-1. It was the first win after two opening losses for the Americans, while Australia finished 0-3.

Casey Dellacqua beat American Meghann Shaughnessy 6-3, 6-4 and James Blake beat Australian Lleyton Hewitt 6-2, 6-2 in a match in which Hewitt, making his return after five months off with a hip injury and surgery, was bothered by an ear infection.

Shaughnessy and Blake defeated Dellacqua and Hewitt 6-3, 5-7 and 10-6 in the tiebreaker in mixed doubles — with Hewitt double-faulting on match point.

"It was not the Lleyton Hewitt of old, he was not at his best," Blake said after the singles match. "I hope he's healthy for the Australian Open."

Russia was to play France and Italy to face Taiwan in two Group B night matches, with the Russia-France match to decide Slovakia's opponent in the final.

Dellacqua, who lost her two opening singles matches, won six of the last seven games of the match to beat Shaughnessy.

"The last few matches I haven't come out with a win but I feel like I'm finally starting to hit the ball better," Dellacqua said. "It's given me a little bit more confidence for the next few weeks leading up to the Australian Open."