Serena Williams continued her march towards Grand Slam history by beating sister Venus in the quarter-finals of the US Open.
The world No 1 and defending champion won 6-2 1-6 6-3 to move to within two victories of securing the Calendar Grand Slam.
During a topsy-turvy opening two sets, Serena broke serve twice in the first set while 35-year-old Venus did the same in the second as she levelled matters by reeling off five games in a row.
In the decider, Serena claimed the only break in the second game and held on to clinch victory in one hour, 41 minutes.
She saved a break point in game three and then sealed the win with an ace.
If Serena can lift the title at Flushing Meadows she will become the first player since Steffi Graf in 1988 to win all four Grand Slam crowns in the same season.
And after beating her sibling in their 27th career meeting, Serena said: “I just was out there to play a really tough opponent today.
“Obviously we are very, very tough competitors on the court, but once the match is over and the second it’s done, you know, we’re sisters, we’re roommates, and we’re all that.
“Down to the match point it just was not easy. It’s probably the toughest match I have played in a really, really, really long time where I wasn’t actually beating myself.
“I was out there facing an incredibly tough opponent. I think against any other player she for sure would have won.”
And should Serena clinch the Grand Slam, what would Venus think?
The older sister added: “It would be a moment for our family. But, at the same time, if it doesn’t happen it’s not going to make or break you.
“We don’t have anything to prove. She has nothing to prove. She’s really the best ever, so what are you going to do?
“Just try to make it. If you don’t, then that’s that and go to the next one. Serena is the best ever because of the level of competition that she’s faced.
“There have been some unbelievable players in the past but I have played in what seems like multiple eras at this point. I have played the best from different eras, as well.
“I have seen the level of competitiveness go up, and I have seen players who are ranked 100, who didn’t believe they could win a match against you, fight you tooth and nail and try to take you down.”
So close was the contest that Serena, 33, won just one more point (76-75) than the No 23 seed.
She now faces unseeded Italian Roberta Vinci, who beat Kristina Mladenovic of France 6-3 5-7 6-4 earlier in the day.
World No 43 Vinci is through to her first Grand Slam semi-final at the age of 32. The pair have met on four previous occasions and Vinci is yet to take a set off the American.
Serena went on: “I’m not going to underestimate her. She’s not in the semi-finals of a Grand Slam for no reason. She knows what to do and she knows what to play.”
