Naomi Osaka said impressing her favourite player Serena Williams was her goal when they met in the first round of the Miami Open.

And the Japanese sensation certainly got her wish with a stunning 6-3 6-2 victory over the 23-time grand slam champion, who was playing her second tournament since giving birth.

Indian Wells champion Osaka ran Williams ragged in an incredible display, recovering from a difficult start to set up a second-round clash with fourth seed Elina Svitolina.

"I was extremely nervous coming on to the court," Osaka said afterwards on Wednesday. "Serena is my favourite player so playing against her was a dream and I was very grateful, but it was even better that I was able to win.

"I kind of wanted to impress her and I wanted to make her say "come on" and I think she did, so I'm really happy about that."

AZARENKA BOOKS KEYS CLASH

Victoria Azarenka breezed through a first-round clash with American teenager CiCi Bellis, recovering from a sticky start to set up a match against 14th seed Madison Keys.

The former world number one won 6-3 6-0 after saving four break points in her opening service game, the two-time Australian Open champion seeking to bounce back from a second-round loss to Sloane Stephens at Indian Wells.

Azarenka and Keys are in the same section as top seed Simona Halep, who will open her campaign against lucky loser Oceane Dodin, who beat Veronica Cepede Royg 6-4 6-7 (3-7) 6-3.

CORNET BATTLES THROUGH MATTEK-SANDS CLASH

Bethanie Mattek-Sands' return to action after a long absence following knee surgery on an injury sustained at Wimbledon resulted in a straight-sets loss to Frenchwoman Alize Cornet.

A 6-2 7-5 loss unfolded over an engrossing one hour and 38 minutes of action at Crandon Park, the 32-year-old American unable to mark her comeback with a victory.

"I'm most happy with the win, but secondly, is to see Bethanie back on court," Cornet said after the match. "She's a great player, and I was very sad last year for what happened to her at Wimbledon."

INJURED ANISIMOVA WITHDRAWS

American teenager Amanda Anisimova pulled out of her second-round match against world number three Garbine Muguruza.

The 16-year-old reached the fourth round at Indian Wells last week but suffered an injury in a win over Chinese player Wang Qiang on Tuesday.

Wimbledon champion Muguruza, the third seed in the draw, now receives a bye into the third round.