Nine-time champion Novak Djokovic will play his comeback match at the Australian Open against Spanish world No.75 Roberto Caraballes Baena on the other side of the draw from Nadal.
Wimbledon finalist and No.19 seed Nick Kyrgios will face Roman Safullin in the first round but has No.9 seed Holger Rune and then world No.6 Andrey Rublev in his path to reach the quarter finals.
Raducanu suffered from blisters before going out in the second round here last year. And the former US Open champion will need to overcome an ankle injury, German Korpatsch and then world No.7 Gauff to reach the third round this year. The American teenager is in good form after winning the title in Auckland last week.
Harriet Dart will face No.32 seed Jil Teichman of Switzerland.