MELBOURNE, Australia – Top seed Serena Williams withstood a tense first set and a late match charge to take out Maria Sharapova, defeating the No.5 seed for an 18th straight time, 6-4, 6-1.

Sharapova came out firing to start, taking an early 2-0 lead on Australia Day, but Williams worked her way into the match in style, saving break points at 4-4 and winning seven games in a row at one stage.

“It was super intense,” the American told Rennae Stubbs during her on-court interview. “She’s an incredibly intense, focused player who was No.1 and won so many Grand Slams for a reason.

“When you’re playing someone who’s so great, you have to come out with a lot of fire and intensity.”

Looking ill at ease with the doctor on court after the first set, Williams was nonetheless ruthless in the second, getting close to a shutout before Sharapova pulled back, even earning two break points for 5-2 as the top seed served for it.

“I’ve been playing this whole week aggressively, but I didn’t start out playing that way today.

“I just knew after the first set that I wanted to start playing the way I have been, that got me to the quarterfinals, so I was just trying to do that.”

Up next for the World No.1 is No.4 seed and BNP Paribas WTA Finals Singapore presented by SC Global champion, Agnieszka Radwanska.

“She’s a great defender and a great girl. I’m going to do my best, and I have nothing to lose,” she said, then addressing the crowd, “Thank you guys for coming out; I hear you all, and it means a lot to me!”

Looking to tie Steffi Graf’s record of 22 Grand Slam titles, Williams is also after a seventh Australian Open title, her first coming back in 2003 to complete her first Serena Slam.

“I’m here all the time; I have so many friends here. This is one of the few stadiums where I feel so welcome.”

Serena on Maria: When I play her, I know automatically I have to step up my game. I think that makes me play better pic.twitter.com/WVYCLVkiNn

— Australian Open (@AustralianOpen) January 26, 2016