Ajla Tomljanovic's Australian Open campaign has come to an abrupt end, with the world No.43 suffering a 6-4 6-0 loss to Paula Badosa in the first round.

Five days after losing to Badosa in straight sets at the Sydney Tennis Classic, Tomljanovic fell short in a bruising first set, then was thoroughly outclassed by the world No.8 in a 24-minute second set late on Monday night.

Tomljanovic, Australia's No.2 behind Ash Barty, had heavy strapping on her thigh and both players had treatment when Badosa, who had shoulder strapping, called a medical timeout in the first set.

"I knew I had to go for my shots," Badosa said.

"I'm a little bit exhausted but it goes how it goes."

Tomljanovic snatched a break in the opening game but then saw Badosa reel off four consecutive games to take the upper hand in the first set.

The Australian bravely fought back, twice breaking Badosa and, trailing 5-4, was about to serve to stay in the set when the Spaniard called for a medical timeout.

During the time out, Tomljanovic had treatment and fresh strapping put on her thigh.

But upon her return, Badosa broke Tomljanovic to snatch the first set, then kicked into another gear.

The Spaniard dropped just nine points across the second set and broke Tomljanovic in the final game to seal victory.

It was a stark contrast to her horror 2021 trip to Melbourne.

Badosa was forced into hard hotel quarantine before testing positive to COVID-19 on her seventh day of isolation, which saw her ultimately spend 21 days in hard quarantine.

At the time Badosa described feeling "abandoned" by Tennis Australia, said conditions were "lamentable" and summarised her stay as "far and away the worst experience of (her) career."

The then-world No.70 lost in the first round but later kicked on to have a breakout 2021, reaching the quarter-final of the French Open, the fourth round of Wimbledon and flying up the rankings.

Badosa will face qualifier Martina Trevisan in the second round on Wednesday after the Italian beat lucky loser Nao Hibino 6-2 6-3.