Lowly-ranked qualifier Monica Puig has broken down in tears of joy after ousting Samantha Stosur from the Sydney International, ABC Australia reports.

Puerto Rico’s world number 94 sent Stosur packing for next week’s Australian Open in Melbourne with a shock 6-4, 6-4 victory at Ken Rosewall Arena on Wednesday night.

Stosur had won all four previous meetings with Puig in straight sets but was unable to find her A game as a first semi-final spot in Sydney in more than a decade beckoned.

Puig needed just two service breaks – one in each set – to prevail in one hour, 28 minutes and was unable to contain her delight after notching one of the biggest wins of her career.

“I’ve been working so hard on every aspect of my game. That’s why I got a bit emotional after this win,” the 24-year-old said.

“It was a tough pre-season for me. It was a difficult year for me last year so it’s really nice to see some of my best tennis so early in the season.

“I’ve always had great respect for Sam. She’s a grand slam champion.”