US Open live: Novak Djokovic v Taylor Fritz latest score and updates from blockbuster quarter-final

That was a very different celebration from Djokovic, but he explains it was for his daughter, whose birthday is today.

Novak Djokovic admits he was “lucky” to win some of the break points he faced and says that either player could have won today. He praises Taylor Fritz and says the American was the better player for long spells of that quarter-final.

“Tough one for Taylor to finish with a double-fault. He didn’t deserve that,” Djokovic adds.

Fritz looks shell-shocked as he comes into the net. He has now lost all 11 matches he has played against Djokovic, who was clinical today.

UNBELIEVABLE! FRTIZ DOUBLE-FAULTS ON THE THIRD MATCH POINT AND DJOKOVIC IS DANCING INTO THE SEMI-FINALS!

Fritz with a poor miss on the opening point. Then Djokovic catches the back of the line and an off-balance Fritz goes long!

0-30. Fritz steadies and comes out on top in a long rally that leaves Djokovic bending over on the baseline.

15-30. Djokovic locks in, pushes Fritz wide, and the forehand miss brings up two match points!

Djokovic nets on the first after a punishing rally!

Djokovic’s return catches the baseline but Fritz hands on! He grinds down Djokovic, who goes long, and Fritz saves a second match point!

That might be Djokovic getting back to his best level and his steers the flicked overhead past Fritz to hold to love.

And now the American will be serving to stay in the match….

Fritz shrugs off a poor miss on the overhead on the opening point to power the ace out wide and hold.

Djokovic could not hide his frustration with two poor returns in a row from 0-15.

Djokovic holds but he’s won just one point against Fritz’s serve so far in the fourth set.

If there would be a time to try and force a look at a break, this would be it.

A little shake of the racket from Fritz. Another solid hold.

if we are thinking about tiebreaks, Djokovic’s record in them has not ben as strong as it used to be recently.

He’s 1-2 at this year’s US Open, While Fritz is 1-1.

Fritz finds some excellent depth on the return to haul Djokovic in from 40-0 up to deuce.

Djokovic replies with a big serve down the middle that Fritz can only get a racket to.

Fritz then nets and the half-chance is gone.

More than the first three sets, this does currently feel as if we’re heading for a tiebreak.