Trouble here as Robin van Persie goes down holding the back of his leg. Is that a muscle strain?

Ah it may just be a dead leg, he got a knee in the back. United do not need him to get injured. Into the last two minutes of normal time...

Neil Stokes:, external This is far too tense. This is worse than the Sunderland game in League Cup. One more goal please.

Paul Oakley:, external Manchester United shutting up shop, times have changed. Not sure it's wise

Olympiakos force a few corners but United get the ball away. It's all getting a bit edgy - four minutes remain now.

Mark Lawrenson
Radio 5 live

"Thankfully for Man Utd - Olympiakos are coming up short so far but they are having lots of possession in midfield."

Darren Fletcher's first touch is a fine one, picking out Wayne Rooney on the corner of the area, but his curling shot is high and wide. Six minutes of normal time left. A goal for either side now would be a knockout blow...

Here's another change for United - Darren Fletcher replaces Danny Welbeck as David Moyes looks to lock the back door. We are into the last 10 minutes now...

Lewis, Wycombe: Regardless of Van Persie's hatrick it will be a crime if David de Gea doesn't get the man of the match for his second half performance.

Adam: In the words of the former manager, it'd squeaky bum time for United.

Mark Lawrenson
Radio 5 live

"It's another top stop from David de Gea, it was hit so quickly and so hard he almost didn't have time to react but he stopped it well."

Olympiakos camped outside of the Manchester United area now. Alejandro Dominguez whips the ball in hard and low, David de Gea does well to push it out and Joel Campbell slams the loose ball over the top.

We have 11 minutes left and it could get nervy at Old Trafford. United can't clear their lines at the moment.

Mark Lawrenson
Radio 5 live

"It's all about the balance for Manchester United. In trying to score the fourth goal they had five players the wrong side of the ball in that Olympiakos attack and almost got caught."

United commit too many men forward and are caught on the counter, Joel Campbell has a dig from 20 yards but scuffs his shot wide. David Moyes' side are caught between two stables here. Do they go for a fourth or shut up shop?

Ashley Young replaces Antonio Valencia, who has lasted well with that massive shiner.

Hats off to Paulo Machado. The Olympiakos man comes on with one of the finest taches ever seen on a Premier League ground. Magnificent.

Fifteen minutes left.

That makes life interesting in Dortmund! Zenit back in the hunt as substitute Jose Rondon beats the offside trap to nod in from close range.

Olympiakos seeing plenty of the ball now as they look for the goal which would turn this tie on its head again. Is that nerves you can hear around Old Trafford?

Yep. Yep it is.

Mark Lawrenson
Radio 5 live

"Patrice Evra again, he is absolutely all over the place, they need to get Danny Welbeck back to help him.

"When Man Utd don't have the ball then Welbeck needs to get back."

Olympiakos press on intently down their right-hand side as we approach the 65-minute mark. There has only been one shot on target in this half - Robin van Persie's goal of the night.

There's the second though - Leandro Salino beats Patrice Evra easily and cuts the ball back for David Fuster, who drills a shot right at David de Gea. Evra is shakey.

Angst on the right wing. First Patrice Evra is booked for a high challenge, and then Leandro Salino is booked for kicking the ball away in frustration.

Evra will now miss United's next game in Europe as we move into the last half hour at Old Trafford.

Mark Lawrenson
Radio 5 live

"It's just important now if you are Patrice Evra playing against Joel Campbell that you say to Danny Welbeck, 'you stay in touch with me and keep an eye on him.'

"If I was David Moyes I would tell Patrice Evra just to sit."

Robin van Persie is the fourth Dutch player to score a Champions League hat-trick after Ruud van Nistelrooy, Roy Makaay (two each) & Marco van Basten.

David Moyes is deep in discussion with Phil Neville on the bench. Bring on Marouane Fellaini and Darren Fletcher to tie it up?

BBC Sport Chief Football Writer Phil McNulty at Old Trafford

"Robin van Persie has taken a lot of criticism this season but is answering back in style tonight. Still a word of caution though for manager David Moyes - this Olympiakos side still looks as if they have a goal in them."