Djokovic and Ivanovic havge known each other since they were children
Top seeds Serbia made a winning start at the Hopman Cup in Perth as Novak Djokovic and Ana Ivanovic proved too strong for Kazakshtan in Group A.
Ivanovic opened the tie with a 7-6 (8-6) 6-1 victory over Yaroslava Shvedova, before Djokovic battled past Andrey Golubev 4-6 6-3 6-1.
Djokovic and Ivanovic then won the mixed doubles 7-6 (9-7) 6-4 to seal a 3-0 victory for Serbia.
Andy Murray and Laura Robson begin Great Britain's campaign on Monday.
Ivanovic has been talking of a return this year to the kind of form that won her the French Open and took her to number one in the world in 2008, before a desperate loss of form and confidence saw her tumble down the rankings.
She had fought her way back to 17th by the end of 2010 but made a nervous start to her first match of the new year, trading five successive breaks of serve with world number 36 Shvedova.
However, Ivanovic edged the tie-break and dominated from then on, saying afterwards: "I think we were both really nervous and it was so hard to hold our serves at first.
"I started to serve a little bit better in the tie-break and then in the second set."
fresh from guiding Serbia to a first Davis Cup win last month,
also made a slow start against the talented Golubev and dropped the opening set, but a break at the start of the second got the world number three back on track.
He dropped just four more games to make a solid start in the build-up to the Australian Open, which gets under way on 17 January.
"We got here just two days ago and it is really hard to get used to the time change and conditions here," said Djokovic.
"In the first set I was too defensive, I was serving a lot of double faults and wasn't playing well, but then I found my pace and I was happy the way I finished off."