Sydneysider Jordan Thompson has broken through for a maiden Australian Open win, defeating Joao Sousa in a gutsy five-set triumph on Tuesday night.

Thompson was down two sets to love against the world no.37 but triumphed 6-7 (2-7) 4-6 6-3 6-2 6-1 in three hours and 21 minutes in hot conditions as the Portuguese complained of dizziness.

The win was the 22-year-old’s first in four outings at Melbourne Park and earned him a match-up with eighth seed Dominic Thiem in the second round.