James Ward-Prowse and Oriol Romeu come on in place of Dusan Tadic and Jordy Clasie. Brings a bit more steel to the Saints midfield.

This is really poor. United win a corner and take it short but Jesse Lingard - one of those involved in the taking - is flagged offside.

Two chances for Southampton! Shane Long rises and meets a corner but heads past the far post. It came off a United man for a second corner, which Victor Wanyama heads past the other post. Saints are getting joy from set-pieces. They have weathered the United storm and are growing as a threat.

Stuart Chaplin: The stage is set at Old Trafford for Charlie Austin to come on and grab a debut goal to remember for Southampton.

Jimmy Armfield
Former England defender on BBC Radio 5 live

"Morgan Schneiderlin has moved up and is supporting the attacking players. In the first-half he played almost on his own with the back four, but now he has got in the box a couple of times.

"The is United's best part of the game, they have upped the temp and suddenly the crowd are behind them."

Darmian is not fit to continue. On comes Paddy McNair to replace him. United's second change.

Matteo Darmian is down after receiving a slam to the chest from Shane Long during a Southampton attack, in which the defender headed away as the Saints striker looked to reach a cross. It doesn't look good for the Italian, possibly a rib injury.

Alex Robertson: think that might have woke the Man Utd fans from their first half nap.

United continue to apply pressure with Saints on the back foot. They win another corner, which the away side half clear only for Jesse Lingard to completely fluff a shot on the edge of the box. Better game now.

United have worked up a head of steam. They spoil it, though, as Daley Blind swings a cross out of play for a goal-kick.

Oh, that was an important interception from Virgil van Dijk to prevent Anthony Martial latching on to Juan Mata's neat pass in the box. The ball deflects back off Martial and ends up in Fraser Forster's hands. United look a lot more dangerous with Mata in behind Rooney.

Ryan Bertrand does superbly to follow Wayne Rooney and slide in to cut out a pass that is designed to reach the England striker as he charges through the middle.

Jimmy Armfield
Former England defender on BBC Radio 5 live

"Perhaps Louis van Gaal is looking for more industry for the front players by putting Juan Mata on. He needs to step up, get one or two shots and try and stretch this Southampton defence."

United have a corner early in the second half. Daley Blind swings the ball in but Jordy Clasie and Virgil van Dijk combine to clear.

We are back under way and United have made a change. Juan Mata is on for Marouane Fellaini. A popular move with the home fans.

Marouane Fellaini turn away now, James Carter has your number...

As you can see from the teams' respective heatmaps, there hasn't been a lot of action in either box.In fact, there has only been six touches in total by a player in the opponent's box.

Image source, Opta

Ian Dennis
BBC Radio 5 live senior football reporter

"Eight hours and 26 minutes without a goal in first-half football at Old Trafford"

Dave Merrington
Former Southampton manager on BBC Radio Solent

"A very disappointing game to watch. Saints deserve at least a point from what we've seen so far. I believe they can come out in the second half and take all three. They can win this. The Southampton forwards have been  ore of a threat than the United ones."