Spain's Rafael Nadal hits a return against Britain's Jack Draper during their men's singles match on day one of the Australian Open tennis tournament in Melbourne on Jan 16, 2023. (MANAN VATSYAYANA / AFP)

MELBOURNE - Defending champion Rafa Nadal dropped a set but prevailed in a battle of fitness against Jack Draper to reach the second round of the Australian Open on Monday with an unconvincing 7-5 2-6 6-4 6-1 over the injured Briton.

Fellow lefthander Draper played superb tennis to level the match at a set all but the 21-year-old soon developed leg troubles and was left groaning in pain as Nadal closed out the match on a warm and sunny afternoon at Rod Laver Arena.

Nadal was broken first game of the final set when Draper punished a dubious attempted drop-shot with a winner but the Spaniard won the next six games in succession to claim the match as the ailing Briton bowed out swinging.

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Nadal, bidding for a record-extending 23rd Grand Slam title, will next face Mackenzie McDonald for a place in the third round.