Serena Williams put emotions aside to win the battle of the sisters again as she beat older sibling Venus in three sets to reach the US Open semi-finals.
The world number one came through the family showdown 6-2 1-6 6-3 and is now just two wins away from becoming the first player since 1988 to seal the calendar grand slam.
It is the 11th time this year Serena has won a three-set match at a major tournament and she will now face Italy’s Roberta Vinci for a place in the final.
Serena has now won nine of the sisters' last 11 grand slam meetings and, in front of a packed out Arthur Ashe Stadium, proved why she has been the dominant force in recent years with another ruthless display.
“She’s the greatest player I’ve ever played in my life and the best person I know,” Serena said.
“It’s going against your best friend and at the same time going against the greatest competitor in women’s tennis so it was really difficult for me today.
“When I’m playing her I don’t think of her as my sister. You don’t really think about it.
“We’ve trained all our lives to be on this court and for us it’s a really great honour.”
As well as aiming to hold all four grand slam titles in a year, Serena is closing in on her 22nd major triumph, which would see her draw level with Steffi Graf’s open era record.
The stakes were high but for four games there was a sense of reverence in the air as the sisters allowed each other to settle, exchanging early punches but reluctant to land a major blow.
At 2-1, however, pleasantries were set aside as Venus slammed an almost disrespectful return for a winner and Serena responded with a whistling passing shot, which she greeted with a passionate pump of her fist.
Holding serve, the set was Serena’s thereafter as a brilliant drop-shot helped her break for 3-2 as she won five games in a row to clinch the set in a brisk 33 minutes.
Hopes of a classic battle had been dented and the early buzz around Arthur Ashe became an eerie hush, with the biggest squeals of excitement saved for a a string of attending celebrities popping up and waving on the big screen.
On court, Venus made another assured start to the second set and this time she capitalised, taking a break in the fourth game after Serena dumped a limp second serve into the net and then holding to love for a 4-1 lead.
Serena unravelled for 15 minutes as she could barely find the court with her groundstrokes while her serve, often interrupted by the crowd cheering her opponent, wobbled with two more double faults.
Serena offered some late resistance at 5-1 set and while she was unable to prevent Venus levelling up, she flew out of the blocks in the decider to take a 3-0 lead.
Venus remained a picture of calm compared to her stomping, raging younger sister and she kept in touch with three consecutive holds to pile the pressure on at 5-3.
Two wayward backhands, however, gave the decisive chance to Serena, who clinched victory with an ace before the sisters finally let their guards down and embraced at the net.