A goal from Scott McTominay in extra time gave Manchester United a 1-0 win over West Ham to book their place in the FA Cup quarter-finals.
David Moyes' side, who lost Angelo Ogbonna to a suspected ankle injury early on, defended resolutely with United carving out few chances.
The hosts' only shot on target in the first half came from a deflected Victor Lindelof header which Lukas Fabianski did well to turn around the post while the Hammers were content with sitting back and defending.
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Moyes brought on Ben Johnson and Ryan Fredericks, as a concussion sub after Issa Diop was involved in a clash of heads with Anthony Martial, and was also forced into another change with Andriy Yarmolenko picking up an injury with former United youth player Ademipo Odubeko replacing him.
But the changes were ineffective and the Hammers continued to offer little as an attacking threat and did not test Dean Henderson at all in normal time.
Ole Gunnar Solskjaer eventually brought on Bruno Fernandes, replacing the disappointing Donny van De Beek, along with Edinson Cavani and saw his side carve out two good chances with Marcus Rashford forcing Fabianski into a good save from close range and Martial sending a header wide as the game headed into extra time.
The deadlock was finally broken when substitute McTominay fired in a first-time strike from close range after Rashford's neat layoff for his seventh goal of the season to put United through.
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The former Ajax man was given a rare start but it is not clear what is his best position is in this team. He sat deeper in the first half and was ineffective and barely touched the ball. He improved slightly when further forward in the second half before being replaced by Fernandes. There was no chemistry with his team-mates, not surprising given his lack of first-team action, he needs a run of games.
Donny van de Beek of Manchester United v West Ham
Image credit: Getty Images
MAN OF THE MATCH - Craig Dawson (West Ham)
Moyes' side may have parked the bus but Dawson was the star man with his blocks and dominance in the air. He had to deal with the loss of Ogbonna and Diop through injury but was impressive throughout the 120 minutes.
Manchester United: Henderson 5, Wan-Bissaka 6, Lindelof 8, Maguire 7, Telles 7, Matic 6, Fred 4, Van De Beek 4, Greenwood 5, Martial 5, Rashford 5. Subs: Shaw n/a, Williams n/a, Fernandes 7, McTominay 8, Cavani 5.
West Ham: Fabianski 7, Dawson 8, Ogbonna n/a, Cresswell 7, Coufal 6, Rice 6, Soucek 5, Noble 5, Fornals 4, Bowen 5, Yarmolenko 5. Subs: Diop n/a, Johnson 6, Fredericks 5, Odubeko 4, Benrahma n/a.
27' - CLOSE! From a United corner, Lindelof's header is tipped away by the keeper around the post!
53' - GOOD SAVE! Greenwood's cross is deflected into the path of Rashford and from close range his shot is blocked by Fabianski.
82' - CHANCE! Telles' cross finds Martial whose header at the near post is well wide.
90'+7 - GOAL! Man Utd 1-0 West Ham (McTominay): Rashford's lay off is fired in by McTominay from close range.
- Moyes has never won at Old Trafford as an opposing manager in 14 games.
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