The Serena Williams juggernaut shows no signs of stopping. Older sister Venus Williams tried her best to derail the Serena train and stop her in the quarterfinal tracks, but, after a minor hiccup, that train rolled along fine again all the way into the semifinals station of the 2015 US Open.

In a match that was hyped up, and then some, both Serena and Venus did not disappoint the capacity crowd at the Arthur Ashe Stadium or the millions watching back at home, showing why, again, they are what modern women's tennis is and has been all about.

At the end of 98 minutes of groundstroking, winner-hitting, ace-serving and double-faulting action, Serena towered just that wee bit over her taller sister, with the younger sibling taking the match 6-2, 1-6, 6-3.

Serena and Venus then embraced each other at the net, with congratulations and commiserations, in their own imitable sisterly-love style, taking court.

"I just said I'm so happy for you," Venus revealed when asked about what was said between the two greats at the net. "I don't remember what else I said after that. Just moments. Just the moment."

"I think I will look back on it fondly," Serena added on that emotional embrace after the match. "It means a lot to me. 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."

Venus believes Serena's ability to play the big points better was the difference between the two in this massive US Open 2015 quarterfinal.

"She has of course a wonderful mental game, but she also has ability to come up with a great shot when she needs it," Venus added. "That's just been the hallmark of her game.

"I thought I played pretty well and served well. Just tried to play aggressively. That's always how I want to play."

And Serena concurred, with the world number one saying her older sister gave her a really difficult time out on court. "It's really great to see her do so well," Serena said. "She was at an unbelievable level today.

"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."

Yeah, so it was just seeing and knowing that she has that level is so good and inspiring, as well, and hopefully it's encouraging for her, too. I think against any other player she for sure would have won.

It is now onto the match against Roberta Vinci for Serena, after the Italian defeated Frenchwoman Kristina Mladenovic 6-3, 7-5, 6-4 to make her first ever Grand Slam semifinal.

Serena is just two wins away from becoming the first tennis player since Steffi Graf in 1988 to win all four Grand Slam titles in the same year.