World number one Novak Djokovic beat Tommy Haas 6-2 6-0 in the opening singles before Ana Ivanovic was even more ruthless in hammering Tatjana Malek 6-0 6-1.
"It's been a great performance from beginning to the end," Djokovic said on the tournament's official website.
"Tommy is always a tricky player and not one to underestimate on the court. I tried my best, I was really focused from the start and I just felt drastically better than in the first few days here in Perth.
"I've been here a few more days and got some rest, got some practice, got used to the balls, the conditions here, so I'm glad I brought Serbia a point."
Haas withdrew from the dead mixed doubles rubber with a toe injury, leaving 16-year-old Australian junior Thanasi Kokkinakis to partner Malek to a straight-sets defeat.
"After you get such a whooping from the world number one, I decided to leave it to someone else," Haas said.
"I'll take a few days off, go on vacation, and think deeply about whether I should play tennis.
"But all joking aside, I did have the injury for the last few days. I wasn't even sure if I could come out today."
Earlier in the day, South Africa beat winless France 2-1 to finish third in Group B after Jo-Wilfried Tsonga retired hurt from the decisive mixed doubles rubber.
Tsonga had earlier beat Kevin Anderson 7-6 (7/4) 7-6 (7/3) to level the tie after team-mate Mathilde Johansson had lost 6-4 4-6 4-6 to Chanelle Scheepers.
But the former Australian Open finalist then appeared to injure his groin in the doubles and indicated he was unable to carry on, with Scheepers and Anderson leading 6-3 1-2 at the time.
"I don't know exactly what I have but I felt something during the singles and the mixed doubles," Tsonga said. "It was a bit more sore during the mixed doubles so for me it was better to quit, for the other team and for Mathilde."