Live Commentary: Flavia Pennetta vs. Simona Halep - as it happened

Hello, and welcome to Sports Mole's live coverage of the US Open semi-final between Flavia Pennetta and Simona Halep at Flushing Meadows.

On Thursday night, a severe thunderstorm put paid to any chances of the women's semi-finals taking place at Flushing Meadows. However, the ramifications of that means that we now now four Grand Slam semi-finals all taking place across the next 10 hours or so. Not bad for a Friday, huh?

Later this evening, we will witness Serena Williams attempt to move ever nearer the calender Grand Slam when she takes on Roberta Vinci, but first up we have world number two Simona Halep, who is looking to reach a Major final for the second time, against Flavia Pennetta, who has ambitions to match the achievements of her Italian compatriot Francesca Schiavone, who won at Roland Garros in 2010.

As far as Halep is concerned, she is looking to join the likes of Serena Williams and Maria Sharapova and form a "big three" at the top of the women's game. Her consistency has kept her at the top of the rankings alongside two of the greats of the game, but a Grand Slam crown would really elevate her to a whole new level. She has the game to remain in the upper echolons of the sport for years to come, but unless she makes a second Major final soon, the pressure will only build on the Romanian.

As for Pennetta, she reached the last four in New York two years ago before running into Victoria Azarenka, but after surprising many with her appearance in the semi-finals this time around, she may feel as though the pressure is off against Halep. That said, when you are not facing either Serena or Sharapova in a Major semi-final, there's inevitably a feeling that you must take your chance. Whether she can or not, only time will tell, but their head-to-head record suggests that she has the game to pull off the upset.

In four previous meetings, Pennetta has won three times, with one of her victories over Halep coming back in 2013. Halep is a different player to the one who competed back then, but the Italian can only take belief from that straight-sets success.

The two players are just going through the final parts of their warm-up, but I can tell you that the sun is out in New York. Hopefully that stays the same for the rest of the day because the weather forecast doesn't look too clever for the weekend.

Right then, we are ready to get going on Arthur Ashe Stadium. It will be Pennetta to serve first.

What a start from both players. Halep started the match with a baseline winner, but back came Pennetta who brought up two game points, The first of taken but only after a brutal exchange that ended with the Italian setting up a winner with a drop shot. No nerves from either player.

Good stuff from Halep, who comes through with the love hold. Pennetta gifted her a couple of points though, especially the last point where a drive volley was fired into the net.

Halep takes the opening point, but she can't take advantage, blasting a makable forehand into the net when having the opportunity to reach 15-30. She misses more chances but an error from Pennetta gives her a look at break point. The ball sits up for her in the middle of the court but a backhand is hooked wide. Big chance missed. The Italian pulls through the game but Halep looks to have a read of her serve.

BREAK! Halep begins her second service game with a well-worked point completed with a drop shot, but three points later, she is facing two break points, which is all her own doing. Pennetta should break on the first but dumps a backhand into the net, but on the second, Halep does the same off the forehand wing. First blood to the Italian.

Pennetta looks in a rhythm now and she breezes to a hold to 15. Halep looks slightly disinterested towards the end of that game. The frustration of losing her serve obviously still bothering her.

BREAK! Halep's game has completely dropped off and a double fault gives Pennetta another look at two break points. She sets up the conversion on the next point but the laziest backhand volley you will ever see goes into the net. Halep hauls her way back to game point, but Pennetta isn't finished and a couple of brutal exchanges end with the Italian on top.

SET! After sending three successive returns into the net, Halep is facing two set points, and even though she saves the first, Pennetta moves a set ahead with a thunderous backhand down the line. A sensational start for the Italian!

BREAK! The ball-striking of Pennetta is relentless and after a backhand winner takes her to 0-30, dominating a rally two points later takes her to two break points. She only requires one though, with Halep netting after more pressure from her opponent.

BREAK! Better from Halep, who is connecting with the ball with much more authority. She moves 0-30 up, which progresses to three break points after Pennetta misses a volley at the net. The break is sealed when Halep gets her opponent on the run, who ends up driving a backhand several yards over the baseline.

Pennetta shakes off the disappointment of the previous game with a winner, but Halep is relentless right now and crushes a forehand winner and serve out wide to reach two game points. The game is sealed with a stunning backhand winner down the line which is celebrated with a fist pump. She's starting to look like the second best player in the world.

BREAK! Pennetta finds her range off the ground to move to 30-15 but Halep is the beneficiary of a lucky net cord to get to 30-30. The pair trade winners to get to deuce, but Halep looks the more confident on the next points. She is crushing everything and her opponent comes up with the error. What a turnaround. High-quality match.

BREAK! Incredible. Just when it appeared that Halep was on her way to levelling the match, she produces a shocker of a service game that ends with a double fault. In all fairness, Pennetta did contribute with some heavy hitting from the back of the court but that was poor from the second seed.

The cross-court weapon of Pennetta is proving to be a destructive weapon and on most occasions, Halep has no answer. A love hold and all of a sudden, the onus is back on Halep.

BREAK! Brilliant from Pennetta, who replies to a Halep drop-shot with one of her own for 0-30 and after bringing up three break points, she connects with a forehand winner down the line. She's two holds away from a place in the final.

A well-directed serve out wide sets up the easy conversion for 30-0 before another cross-court backhand creates three game points. Halep then fires a backhand out and that makes it 15 points in a row for the Italian. That's ridiculous for a Grand Slam semi.

MATCH! Halep takes the opening point but two stunning winners and a double fault lead to Pennetta creating two match points. Halep comes up with a magical point to save the first, but on the second, Pennetta crushes a forehand winner onto the line to reach her first Grand Slam final in just under an hour!

That was special. So, so special. Halep would have been full of belief after seeing off Azarenka but she had no answer to the hitting of Pennetta in that match. The 26th seed reaches the final but who will she play? It will be either Serena Williams or Roberta Vinci. That will be coming up shortly. Goodbye for now.