Serena Williams tip-toed her way into the semi-finals of the WTA Sony Ericsson Open with a 4-6 7-6 6-2 victory over Li Na.
Serena and Venus to clash for place in Miami final
Serena Williams tip-toed her way into the semi-finals of the WTA Sony Ericsson Open in Miami with a 4-6 7-6 6-2 victory over Li Na.
The American pulled herself together after a shocking start to level the match in a second set tie-break before claiming a hard-fought win after more than two hours on court.
The victory sets up another exciting semi-final clash between the Williams sisters after Venus came through a comfortable 6-1 6-4 winner over Czech Republic's Iveta Benesova.
However, it was nearly a different story after China's Na dominated Serena's serve in the opening set to race into a 5-0 lead with three breaks before the world number one hit back.
She got back two of the breaks but the world number 40 held her nerve to clinch the set.
Decider
Neither player was able to force a break in the second set - Na unable to convert any of her six opportunities on her opponent's serve as it went to a tie-break.
Once there, Williams was dominant as she gave up just a single point to take the match into a decider.
And the loss of the set appeared to drain the unseeded Na, who immediately relinquished her serve in the opening game of the third, and with Williams now oozing confidence on her own delivery the match came to a swift conclusion.
"I wasn't as upbeat and spirited as I normally am," admitted Williams. "I think maybe one or two 'come ons' during the whole match which is not really normal for me.
"I am always going to be up for V (Venus). Because she's playing really well and always playing me super tough.
Comfortable
"It is like I automatically have to be on a different level because she's already playing a different level.
"Her balls are harder and her serve is way bigger. It is like I have to be there. And it is super fun to hit those serves that are like 120. It is frustrating but at the same time fun."
In contrast, sister Venus started confidently in the first set, breaking Benesova twice early before finishing off the set with a powerful ace.
She took her foot off the gas in the second, allowing Benesova to go 3-0 up and then giving her three break points in the fourth game.
But she found her composure and ran out a comfortable winner to book a semi-final against Serena on Thursday.
Venus has a 10-9 record against Serena but earlier this month lost to her in an exhibition match at Madison Square Garden.
