Perth:The United States will be chasing their fourth Hopman Cup title in six years when they play top-seeded Serbia in Friday's final of the mixed teams tournament.
The two nations went through their group matches undefeated, but took very different paths to the final.
The Americans cruised through with barely a hiccup, despite Serena Williams missing their opening tie and being substituted by Meghann Shaughnessy.
The Serbs on the other hand had to rely on an injured Jelena Jankovic hobbling through two three-set mixed doubles wins to secure their berth and her fitness is likely to be a big factor in the final.
Although Serbia won their first two ties, they needed to beat Argentina in the final group clash on Thursday to deny France the top spot.
Jankovic, for the second day in a row, was unable to complete her singles match, retiring when a set up against a struggling Gisela Dulko.
Novak Djokovic then levelled the tie with a straight sets win over Juan Ignacio Chela, 6-2, 6-3.
Despite her injury, Jankovic again fronted for the doubles and teamed with Djokovic for the crucial win, secured in a tie-break, 6-1, 3-6, 7-6 (10-4).
Jankovic paid tribute to Djokovic after the win. "I just have a superman partner," she said. "I want to thank him for making such an effort. Thanks to him we are in the final.
"Even though I am injured and in pain, I want Serbia to be the best and I will try tomorrow."
Sania-Bopanna excel despite loss
Sania Mirza and Rohan Bopanna kept their unbeaten record in doubles on Thursday though India failed to get into the final of the Hopman Cup.
Even as India was playing the Czech Republic, the United States on an adjoining court blanked hosts Australia to book their ninth entry into the final of the tennis tournament.
However, Sania Mirza would have been disappointed at losing to Lucie Safarova, who she had beaten in the same competition last year.
Sania, who needed on-court treatment for a back problem, lost in three tough sets. She went down 2-6, 6-4, 6-3.
Safarova got off to a flying start against Mirza, winning the opening set 6-3. The battle between the world's No. 23 and 31 then heated up when Mirza levelled the match by taking the second set 6-4.
Safarova proved too strong in the third to record her first singles win of the week, clinching the deciding set 6-3.
Then Tomas Berdych beat Bopanna 6-4, 6-0 to ensure an unassailable 2-0 lead.
The win in the last tie was a small consolation for the two losses.
Safarova had struggled with a slight illness and leg injury in her opening two losses to Australia's Alicia Molik and Serena Williams, while Berdych began with a win over Peter Luczak.
Later Berdych was forced to withdraw from his match with American Mardy Fish due to a stomach virus.
Having recovered from the bug that kept him from playing on Monday, Berdych overcame a slow start against Bopanna to win in straight sets.
Bopanna held a 2-0 lead to start the match, but Berdych responded by winning the next five games to eventually take the set 6-4. He then dominated the second, taking it 6-0.
However, the Indians made sure they left Perth undefeated in the doubles, beating Safarova and Berdych 6-3, 6-2. The Indians have not lost any doubles match at Hopman Cup in the last two years.
India finished second in Group B and the Czech Republic fourth.
Meanwhile, Serena Williams and Mardy Fish booked the US a place in the Hyundai Hopman Cup final by winning their singles matches over Australia's Alicia Molik and Peter Luczak.
The victory in Thursday's tie left the Americans undefeated at the event despite Meghann Shaughnessy substituting for Williams in the opening tie on Saturday.
Williams' 6-2, 7-6 win over Molik in front of a jam-packed Burswood Dome Centre Court sealed the United States' place in the final.
Fish and Luczak then had a ding-dong battle though a final spot was no longer riding on the result. Both sets went to a tie-break, with Fish winning the first 7-5 and second 13-11.
In the mixed doubles, Williams and Fish had a good preparation for the final beating Molik and Luczak 6-2, 6-3.
It will be the country's ninth appearance with Williams and Fish trying to provide the US with its fifth Hopman Cup crown.
US, Serbia to battle in finals