Image source, PA

Chris Adams: Pulis tactically inept. The game's moved on and he's still using tactics from the dark ages.

Chris Wakeman: 'Posh' playing like the premier league side in the opening 10 mins!

Paui Dempster: One of my biggest pet hates is subs not being ready to come on. How can you be sat there without your shirt, boots & shin pads on?

Here he is! Not exactly sure what Sebastien Pocognoli was doing. But he's pulled up his socks, taped up his jewellery and is finally returning Albion to their full complement.

Albion still haven't made a change though - they're down to 10 men. Sebastien Pocognoli is taking an age to get ready. He'll be feeling the full Pulis glare in a minute. 

Gareth McAuley's night is over. The Northern Irishman sprints back from an Albion corner to chase a quick Peterborough break, then suddenly pulls up. Ping! Hamstring gone. He goes down, grimaces, and knows he is heading back down the tunnel.

Image source, AP

There is football in Spain today as well where Gary Neville's Valencia take on Barcelona in the Copa del Rey semi-final second leg.

Neville is under real pressure, especially having lost the first leg 7-0.

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Chris Forrester was being talked up as a Michael Carrick-type player before kick-off. He shoots more than the Manchester United man. The Irishman's 20-yard effort is ambitious, but forces Ben Foster into action.

Still all Peterborough. Even James McClean is back defending. The Republic of Ireland winger slides in dangerously to carve up another Posh attack.  

Martin Keown
Former Arsenal defender on BBC One

"It's great play from Martin Samuelson, he finds a pass and James Chester has come from nowhere to get that block in. A great start from Peterborough - there is a real energy about them."

Peterborough clearly have watched that video nasty of Albion's defending at Newcastle - they're all over them in these opening stages. 

On-loan Posh forward Martin Samuelsen - not the product of a well-known tabloid journalist - dances into the Baggies area, selflessly laying off the ball to the wonderfully-named Harry Beautyman.

He strikes a, er, beauty but sees James Chesters wonderfully block by throwing himself in front of the ball.

Alan Shearer
Former England captain on BBC One

Image source, Getty Images

"West Brom's back four were all over the place against Newcastle at the weekend. That has to give Peterborough encouragement. 

"West Brom are the lowest scorers in the Premier League. I know this is different but Peterborough have a real chance."

Image source, Getty Images

Peterborough winger Jon Taylor was the man whose late equaliser set up this replay and he tees up the home side's first attack. He tries to whip in a cross from the flank, winning a corner.

But the League One side cannot convert the set-piece, the ball pinging around the away box before Albion clear.

Peterborough midfielder Jack Collison on BBC One: "We have a real good young squad. 

"Chris Forrester is one to watch. He makes the team tick like Manchester United midfielder Michael Carrick. 

"I think there will be plenty of goals."

Early chance for Albion. The visitors win a free-kick about 25 yards out close to the left touchline. Send up the big men! 

James McClean whips in the set-piece looking for the skyscraper figures of Gareth McAuley and Jonas Olsson. But his delivery cannot be met by an Albion player - or anyone - as the ball trundles through the packed penalty area. 

Image source, Reuters

Albion, decked out in their red and black changed strip, have the honour of starting this fourth-round replay under way.

A fifth-round trip to Championship side Reading awaits the winners... 

Almost show-time. Referee Mike Jones leads both teams out of the tight London Road tunnel to a wall of noise from the home fans.

Big Bazza Fry is having a word with the BBC cameras on the London Road pitch. "Ahhh the romance of the cup," he crows.

He's sounding more like an Eastenders pub landlord by the day.

"Up the Posh," screams the Posh director of football before disappearing into the stand. What a character.

Image source, Reuters

Peterborough boss Graham Westley, speaking to BBC Sport: "The players are an ambitious bunch but they know it is one win at a time and they know this game is not going to be easy.

"Top players are top players for a reason. You underestimate them at your peril."

Peterborough midfielder Jack Collison on BBC One: "It's a massive game. There is a real buzz about the place. The lads only know one way to play. They are really going to go for it. 

"Graham Westley is a massive character. He is very intense but his enthusiasm rubs off on the lads. You want to do well for him."

Alan Shearer
Former England captain on BBC One

"If West Brom play anything like they did against Newcastle at the weekend there is every chance of an upset."