Tranmere are still creating chances. Kieron Morris is at the back post with a header six yards out, but he can't steer it goalwards. That was a good opportunity. How many more will they get?

Tranmere's Neil Danns, who could've been the hero with a chance in injury time to score a winner, is replaced as Micky Mellon looks for some fresh legs for the final 20 minutes of this one. Harvey Gilmour comes on.

Jose Holebas turns on the style as the Watford defender makes a storming run from the halfway line to the edge of the box, but then loses any composure and the chance evaporates.

Stephen Warnock
Ex-Liverpool defender on BBC Radio 5 Live Sports Extra

Really good play from Whelan, nips inside and it's an even better save from Davies because Andre Gray just runs right across his eyeline and I think it might put him off but it's a fantastic save to his right-hand side.

So close to a Watford lead. Callum Whelan feints to shoot, then does so on the edge of the penalty area and it's going in, but Scott Davies dives to his left to push it two-handed away for a corner.

Holebas' delivery from the right causes Davies a problem as he fumbles it, but he gets away with that one.

It's a good punch from Tranmere keeper Scott Davies, who under pressure, clears the danger from Jose Holebas' inswinging corner.

A cross into the Tranmere penalty area, Andre Gray gets to it and wins a corner.

Stephen Warnock
Ex-Liverpool defender on BBC Radio 5 Live Sports Extra

I've never seen that before! It was incredible!

A rubbish start to extra time. Andre Gray tries to play it back to a Watford team-mate who is standing outside the centre circle. But Gray gets it all wrong, just nudges it backwards and then plays it again.

As no-one else had touched it, it's a free-kick to Tranmere. A tired-looking kick-off that one.

So who has the most energy left in the tank? We saw a few Tranmere players go down with cramp, but both sides have to dig deep for another 30 minutes on this energy-sapping pitch.

Stephen Warnock
Ex-Liverpool defender on BBC Radio 5 Live Sports Extra

On that late chance for Neil Danns...

The anticipation by Neil Danns - he believes the Watford defender is going to miss the ball. He jumps on the second ball again and he's one-on-one, ducks left, jinks right, hits the shot just past the far left post. Tranmere fans thought that was going to be the goal to send the team through.

Get comfortable. We've got another 30 minutes, and maybe penalties after that.

The free-kick, in the centre circle, is taken by goalkeeper Scott Davies aimed towards Peter Clarke, but Watford clear.

But the ball comes back at them and it's a chance for Neil Danns to win it for League One Tranmere, he cuts on to his right foot inside the penalty area, shoots at goal... but just wide.

A free-kick close to the halfway line for Tranmere. The big men go forward. Late drama?

Liam Ridehalgh swings a cross into the Watford penalty area but well played Daniel Bachmann as he takes the ball above his head to ease the pressure.

Stephen Warnock
Ex-Liverpool defender on BBC Radio 5 Live Sports Extra

Brilliant skill by Danns and it's even better defending by Bayli Spencer-Adams. It's a fantastic block, last ditch. You just wonder if Danns would have made that run five or 10 minutes ago, would his legs have kept up with him a little bit more. He just looked tired taking that last touch.

Is this the moment that is taking us to extra-time? Two minutes plus injury-time for a winner or it's 30 minutes more.

Tranmere's Neil Danns goes on a jinking run and gets into the penalty area but just about as he is set to strike at goal, Bayli Spencer-Adams comes up with a perfectly-timed sliding challenge. Top defending from the Watford man. He had to be spot on, and he was.

Stephen Warnock
Ex-Liverpool defender on BBC Radio 5 Live Sports Extra

I'm just wondering what Watford are going to do now? They might try and go a little bit more direct to try and win those second balls. Tranmere are just looking a little bit tired in midfield, with Perkins and Danns, they've covered so much ground tonight.