That's all from us today.

Thanks for joining us! We need coffee.

We'll be back tomorrow for the men's semi-finals, kicking off with Rafael Nadal v Juan Martin Del Potro at 21:00 BST.

Serena Williams will be playing in her 31st Grand Slam final on her home turf in New York.

Naomi Osaka will be playing in her first Grand Slam final against one of the greatest players in the history of tennis.

No biggy.

Russell Fuller
BBC tennis correspondent on 5 live sports extra at Flushing Meadows

Osaka is one serious player. We were thrilled with how she played at Indian Wells and here she is in New York, in one of the Grand Slams and she is in the final.

Oh, hi Naomi!

Image source, Getty Images

Naomi Osaka in her post match interview: "This is going to sound really bad but I was just thinking I really want to play Serena.

Asked why: "Because she is Serena. What do you mean?!"

On the match: "It still feels really weird. I have never beaten Madison before so I am happy to get through this match because she is a very good player.

"I thought I was visibly shaking and stuff but I tried to think I have never been in this situation."

Asked what was in her mind when serving out: "Don't double fault."

Asked to give a message to her mother: "Mom, I did it. I love you. Thank you."

Asked to give a message to Serena: "I love you."

Anything else to add?: "I love everybody."

Now, we all know how entertaining Osaka's post-match interviews can be. Brace yourselves, this one could be EPIC.

(And very giggly)

Jeff Tarango
Former professional tennis player on BBC Radio 5 live sports extra

I don't know if Osaka believes she can beat Serena but she is playing well enough to do so.

Russell Fuller
BBC tennis correspondent on 5 live sports extra at Flushing Meadows

Osaka was on Madison Keys' patch but she has come through in flying colours.

Madison Keys is devastated. She shakes Osaka's hand, waves to the crowd and marches straight down the tunnel.

Osaka has sunk into her chair with relief and probably disbelief. Her mum is pouring her eyes out and the coaching box are posing for celebratory photos.

What a moment.

Osaka's first forehand goes long but she makes no mistake the second time of asking. Another big serve down the T gives her the lead.

Then Keys' backhand goes wide.

Two match points for Osaka!

Russell Fuller
BBC tennis correspondent on 5 live sports extra at Flushing Meadows

Madison Keys needs this Arthur Ashe crowd now.

Jeff Tarango
Former professional tennis player on BBC Radio 5 live sports extra

Usually a player has a different 'serving out game' than they have used in the rest of the set so that you don't use the same pattern. Until about the seventh or eighth point a player will know what serve they will play.

*Reminder to Naomi's mum to keep breathing*

Japan's 20-year-old Naomi Osaka will now serve for a place in the US Open final against Serena Williams.

40-0 in the blink of an eye.

And an ace down the T. Game Keys.

Keys returns long on the second serve...

And Osaka smashes a backhand winner! She holds! NERVES OF STEEL.

One more service game to go!!

Osaka doesn't hold back. She smashes a few forehands and hits a winner into the corner. Deuce.

Keys return is then long to give Osaka the advantage.

But the American opens up and unleashes a superb forehand winner down the line. Deuce again.

Keys gets lucky when her backhand bounces off the net post and into play. Osaka swats it away with a backhand winner.

But it's shortly a 13th break point for Keys...

Pressure's on.

A smashing second serve return from Keys. 30-15 to the American.