Naomi Osaka began her quest for a third Australian Open title with a 6-3, 6-3 victory over Camila Serrano in the first round on Rod Laver Arena.
The 13th seed hit 19 winners, won 83 percent of her first-serve points and broke the Colombian four times as she won for the 23rd time in her last 24 matches at Melbourne Park.
Osaka took the first five games of the match before Osorio clawed her way back into the set before the defending champion closed it out in 34 minutes.
The second set was much closer as the Colombian had early opportunities to break, but Osaka saved them and broke twice more to close out an impressive performance.
Four-time major champion cruises into second round
It didn't take long for Osaka to establish her dominance as she built a 3-0 lead behind her forehand and she extended it after denying Osorio a pair of game points to eventually break again.
After another hold made it 5-0, the world number fought back and was helped as Osaka committed a slew of unforced errors. A hold to love made it 5-3 and she held a pair of break points to get back on serve, but couldn't convert as the defending champion eventually closed out the set.
The Colombian created two break chances in the second game of the second set, Osaka saving both. The 13th seed then broke, aided by three double faults from Osorio and consolidated her lead for a 3-1 advantage.
Credit to Osorio for staying close as she found a rhythm on serve, but serving to stay in the match at 5-3, she fired a forehand into the net on match point as the four-time major champion advanced.