Serbia needed a champions tie-break in the mixed doubles to beat Australia after Novak Djokovic suffered a shock defeat against Bernard Tomic in the Hopman Cup in Perth.

Djokovic lost in straight sets to Tomic, and Serbia had to rely on Ana Ivanovic to beat Ashleigh Barty before edging to a 2-1 win in a tight mixed doubles.

Tomic was never troubled against Djokovic and an upset in Group A looked on the cards.

But Ivanovic made short work of her young opponent and coasted to a 6-2, 6-3 victory.

The Serbians then teamed up in the mixed and grabbed the first set 6-4. But Tomic and Barty battled back to take the second 10-8 on a tie-break.

That resulted in a champions tie-break which Djokovic and Ivanovic won 10-6 to record Serbia's second group win of the tournament.

Elsewhere, Francesca Schiavone and Andreas Seppi earned Italy a 2-1 win over Germany in the other Group A match.

Italy had to come from behind to clinch the tie after Seppi lost his singles to Tommy Haas.

Schiavone defeated Tatjana Malek before teaming up with Seppi to win the mixed doubles.

Seppi had been in a position to win both sets against Haas before losing 7-6 (7/3), 7-6 (9/7). Schiavone then defeating Malek 3-6, 6-3, 6-3, while the doubles went 6-4, 7-5 in Italy's favour.

The win was Italy's first of the tournament after defeat to top-seeds Serbia, but the loss for Germany left them bottom of Pool A and with no chance of making Saturday's final.