Nadal to face Tomic in Australian Open first round
World number one Rafael Nadal serves during a practice session for the Australian Open tennis tournament in Melbourne on January 9, 2014
The Spaniard, who won the tournament in 2009 and missed last year's opening Grand Slam through injury, faces a testing first round encounter against the world number 52.
Tomic was due to play Ukraine's Sergiy Stakhovsky in the Sydney International semi-finals later Friday in the defence of his title.
In the draw made in Melbourne on Friday, Nadal was seeded to face Argentine fifth seed Juan Martin del Potro in the quarters.
Serbia's world number two Novak Djokovic, bidding for his fifth Australian crown and fourth in a row, was drawn to face Swiss Stanislas Wawrinka in the last eight.
Djokovic must first play Slovakia's Lukas Lacko in the opening round in the bottom half of the men's draw.
Britain's three-time runner-up Andy Murray was seeded to face 17-time Grand Slam champion Roger Federer in the quarter-finals in the top half of the draw.
Wimbledon champion Murray will play Japan's Go Soeda first-up. Federer, a four-time winner in Melbourne, meets Australian wild card James Duckworth in the opening round and could face Frenchman Jo-Wilfried Tsonga in the fourth round.
Spanish third seed David Ferrer was drawn to face Czech seventh seed Tomas Berdych in the other quarter-final.
Unseeded Australian Lleyton Hewitt was in Nadal's side of the draw and faces Italian 24th seed Andreas Seppi in the first round.