Last year's French Open winner Ostapenko has thus failed to advance to the best of 32 at the tournament.
Ostapenko gained 130 WTA points for advancing to the third round, just like she did last year at the Australian Open.
While serving was feeble on both sides of the court in the first set, Ostapenko made more errors.
She did however dominate the second set, but broke down in the final set after the seventh game, which lasted for 12 minutes.
This means both Anastasija Sevastova (WTA 15) and Ostapenko are out of this year's Australian Open.