The two Huddersfield changes have lifted the crowd and made an impact for sure. Nahki Wells has already pressed John Stones into an error while Elias Kachunga beat his man on the right before running into Fabian Delph. 

Oxford are giving this a real good go. They break down the right and whip a low cross into the corridor but having judged his run between two markers well, Antonio Martinez pokes his shot from eight yards out wide of goal, via a deflection. 

But it's Huddersfield who blink first, as they bring on their two top scorers. On come Elias Kachunga and Nahki Wells for Rajiv van La Parra and Joe Lolley.

Manchester City continue to see most of the ball but continue to fail to do anything with it. Nolito looks the most likely man. Will Pep Guardiola make a change? He has Kevin de Bruyne, Kelechi Iheanacho, Raheem Sterling and Leroy Sane available.

I've seen worse benches. 

Image source, Rex Features

Danny Mills
Ex-Man City defender on Final Score

Cooper dives in on Musa. The referee has no option.

It was a needless challenge.

Image source, Reuters

Suddenly it is a card-fest. Ron-Robert Zieler misjudges his distances and steps just outside his box after collecting the ball on the right side of the box. Yellow is the result, along with a Millwall free-kick.

They chip the ball into the box but Leicester dig in to clear.

Now Millwall's task is a very tough one. Jake Cooper - the man who was booked for charging in on Leicester keeper Ron-Robert Zieler at the end of the first half - lunges in crudely on Ahmed Musa as Leicester were looking to break. Out comes a second yellow, followed by red. He can have no complaints. 

Golden opportunity for Leicester to advance to the last eight now.

Image source, Reuters

Jesus Navas is the most consistent winger I've ever seen at hitting the full-back in the shins with a cross. He does win a corner which John Stones heads wide. Game in a bit of a cul-de-sac. 

Kevin Kilbane
Former Huddersfield winger on BBC Radio 5 live

What are you getting from Jesus Navas? He has been extremely poor.

He has so much pace and he wants the ball to his feet but he can actually continue his runs off the ball then demand the ball.

Danny Mills
Ex-Man City defender on Final Score

If Millwall get one goal, Leicester will capitulate. Even if it is a different side, the whole club is down in confidence.

A lot of these players will be disgruntled thinking, 'the first team are losing week in, week out, why can't I get in the first team?'

Today is their opportunity but I am not seeing anything to say these players should be in the first team.

Image source, Reuters

Ahmed Musa is certainly giving himself a chance of scoring. Unfortunately, his execution has been poor so far. His eighth shot is straight at Jordan Archer, who saves. 

Adama Traore is a full-back's nightmare. He's not only quick, but built like a middleweight boxer. Even when he slips he is strong enough to win the ball back off Marvin Johnson before driving a low cross that almost finds Viktor Fischer before being cut out. 

Image source, Getty Images

Much has been made of Huddersfield manager David Wagner and his links with Jurgen Klopp and his side share a lot of DNA with the current Liverpool team. They press relentlessly from the front, with out-and-out pace in the men just behind the striker. 

Ahmed Musa is into his stride straight from the start of the second half at the Den. He buys himself a yard on the edge of the box but his low shot is blocked by Jake Cooper.

Image source, Rex Features

Dion Dublin
Former Leicester and Man Utd forward on Final Score

Huddersfield have had their fair share of the possession. 

They have had a couple of half chances and got the ball into the box. 

They are still in this game.

Oxford do indeed come out with intent, breaking down the left before having a low cross put behind. The resulting corner causes a bit of panic in the Boro defence before a home defender hooks clear.

Dion Dublin
Former Leicester and Man Utd forward on Final Score

Middlesbrough have got to not rest on their laurels and think the game is done. 

Oxford will come out flying. They have got 45 minutes to save their competition. 

Image source, PA

That's more like it Sergio! Aguero picks the ball up maybe 35 yards out on the left, cuts inside and beats two men before a low shot is pushed clear by Huddersfield's impressive young stand-in keeper Joel Coleman. 

Image source, Getty Images

And we are under way again. One tie looks to be over. The other two are there for the taking. 

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