Here's that overturned red card from earlier.

Coin toss.

Simon Stone
BBC Sport at Old Trafford

Watford don't actually have to win tonight, a draw and penalties would be enough.

It's probably a good job. Their last - in fact their only - success on this ground was in an EFL Cup tie in 1979, during the Graham Taylor era.

Taylor was manager for 10 years. Watford are onto their fifth in since January 2018.

Ian Wright
Former Arsenal striker on BBC One

With his form at the moment, you would like to see Alexandre Lacazette get one of those chances. You have to credit to Newcastle at this point because they have defended really well.

Plymouth have a free-kick on the far right and it's whipped into the box. The cross is good but Will Aimson heads over.

He has his head in his hands because he thinks he should have done better.

Plymouth are making a few more changes now too. Defender Scott Wootton is among them. They are trying to see this one out.

Kieran Tierney tries to get in on the left and ends up lashing into the side-netting from a tight angle.

Gary Lineker
Ex-England striker on BBC One

Both sides might as well just give us a penalty shootout now - we have stuck out it for so long!

Calum If it carries on like this neither side will score even in the inevitable penalty shootout...

OK, we're off in the second half of extra time...

Final 10 minutes or so for Huddersfield. They are making their final changes.

Talented youngsters Myles Bright and Etienne Camara are on.

Steve Wilson
Match of the Day commentator

Steve Bruce can take a lot of positives from this game - whatever the outcome for Newcastle.

But...the games are coming thick and fast and with Newcastle in action again on Tuesday, that's not much of a break.

Newcastle are sitting deep again now. Trying to get to the break in extra time.

Bukayo Saka sizes up a free-kick from distance and decides to clip it to the back post, where Andy Carroll heads clear.

And that's the interval.

Sam Folarin curls it in early from the right but it goes all the way over to the far side. Middlesbrough pushing here...

Danny Murphy
Former Liverpool and England midfielder on BBC One

Matt Ritchie puts his body in the line for Newcastle and that's what you have got to do!

Conor Grant is allowed to run all the way into the box and get a shot away under relatively little pressure.

It's through the legs of a defender but rolls harmlessly wide.

Danny Murphy
Former Liverpool and England midfielder on BBC One

The one thing with Bukayo Saka is he is always trying to make things happen, nice and positive in his play, able to go at people and get in behind.

Heroic defending from the visitors. They're being tested now. Nicolas Pepe plucks the ball out of the air and wriggles on to his left foot inside the box, but Matt Ritchie throws himself in front of the shot.