Petra Kvitova produced a gruelling comeback to defeat home favourite Ashleigh Barty and win the Sydney International final 1-6 7-5 7-6 (7-3).

Fifth seed Kvitova lost the first set and fought back from 3-0 down in the decider to force a tie-break, where she again had to rally from a losing position to extend her winning run in WTA Tour finals to eight matches.

The Czech will head into the Australian Open in high spirits having reclaimed a title she last won in 2015.

Australian Barty looked ready to race to victory when she took the opening set after just 26 minutes, a long backhand from Kvitova seeing her drop serve for the third time.

Some powerful groundstrokes were key to Kvitova's recovery, the two-time Wimbledon champion able to break in the 11th game of the second before serving out to level the match, a crisp forehand clipping the baseline to convert her second set point.

Momentum swung back to Barty but Kvitova managed to restore parity before twice passing up a chance to serve out the match.

Kvitova fell 3-1 behind in the tie-break but again fought her way back and a whipped forehand from out wide wrongfooted Barty and clinched her first title of 2019.