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Match kick off
Martial is slipped in down the right by Mata and without looking up, puts the ball straight into the danger area towards Rashford, who's already ahead of the play and can't rescue it. West Brom scramble the chance away before anyone can pick it up at the far post.
BIG SAVE! Moments after Townsend gets into the box but just overruns it behind, West Brom get it right by slipping the ball into Grant, who's got away from Lindelof. He looks for the far post and a slight touch off Lindelof, and then De Gea's palm, turns it behind for a corner.
OVER! West Brom pass up another chance. A short corner is whipped into the middle and Ivanovic, who gets under the ball and skies his header behind. The warning signs are racking up for Manchester United.
SENSATIONAL! Fernandes cuts in off the left flank and lifts a stunning ball to Mata on the right of the box.
He looks to square for Martial to tap home but Townsend keeps his head to hook it away before Johnstone punches clear.
Second half is underway.
Man Utd have won just one of their last 13 Premier League home games that have been level at HT (D8 L4), winning none of their last nine at Old Trafford that have been 0-0 at the interval.
NO PENALTY! Coote has a look at the review monitor - and changes his mind.
If that's a clear and obvious error, I'm winning the next series of I'm A Celebrity. For whatever reason David Coote was taken off tomorrow's Liverpool vs Leicester VAR role, but it hasn't done much to keep him out of the spotlight.
GOAL! MAN UTD 1-0 WEST BROM (Fernandes pen 56)
WIDE! Pereira tries an effort which is ambitious to say the least and is never in danger of levelling the scores.
We'll see a lot about what West Brom are made of having played so well for 55 minutes, and with a sense of injustice in their stomachs.
Van de Beek and Cavani are being readied for the hosts. You can definitely see the sense in the former given United need more control in the middle.
SUBS! Robson-Kanu comes on for Diangana and Robinson for Grant, with Cavani on for Mata for the hosts. Martial likely to drift wide now.
SO CLOSE! West Brom can't buy a break here. Robinson is inches away from a perfect introduction from the bench, taking the ball from Townsend and bending it from the corner of the box towards the far stancheon, and catching the crossbar with De Gea beaten.
So close to an equaliser.
WHAT A STOP! Johnstone doesn't deserve to be on the losing side here. United flood men into the box with West Brom having to commit in their search for an equaliser.
When Fernandes rolls the ball across to Rashford at the back post, he looks to hook it past Johnstone from close-range and pulls another stunning stop out of the goalkeeper, who has no time to think about it at all but puts it behind for a corner.