Last updated on .From the section FA Cup

Romelu Lukaku scored his 12th goal in 11 FA Cup games as an uninspired Manchester United beat Brighton to reach the semi-finals.

Lukaku headed in a first-half cross from Nemanja Matic, who sealed victory late on when he nodded in Ashley Young's free-kick.

Victory maintained realistic United hopes of a trophy after Tuesday's Champions League elimination by Sevilla, as well as their record of not having conceded a goal in this season's FA Cup.

But Jose Mourinho's side struggled through the second half, as Brighton had several chances to force extra-time before Matic finally put the tie to bed.

Home fans, angry about the unadventurous performance in defeat by Sevilla, became increasingly tetchy as the game wore on.

Jurgen Locadia, Brighton's £14m record signing, had four chances to equalise, with goalkeeper Sergio Romero saving the first two before the Dutchman headed over wastefully from Solly March's cross.

He then had a shot blocked by Chris Smalling, who had hit the post for United before Lukaku's goal.

Mourinho's 'heritage' players see him through

Romelu Lukaku's goal was his 25th in 44 appearances for Manchester United

"One day, when I leave, the next Manchester United manager will find here Lukaku, Matic, of course De Gea from many years ago. They will find players with a different mentality, quality, background, with a different status, knowhow."

In the midst of an extraordinary 12-minute defence of his United record on Friday, in which he referred repeatedly to "football heritage", Mourinho mentioned two outfield signings as evidence that he has improved the team since his arrival in May 2016.

He might, then, have felt some satisfaction that Lukaku and Matic were the players whose goals took United to April's Wembley semi-finals. In truth, there was little else for him to be pleased about.

Lukaku's opener - maintaining his record of having scored in every round of this season's FA Cup - came at a good time for United; Brighton had just enjoyed a sustained spell of possession.

He got in behind Lewis Dunk to score from a terrific Matic cross for his 25th club goal of the season - although there was a key role played too by Luke Shaw, a Louis van Gaal signing. The left-back ran at Solly March, pinning back the winger, before laying back into space for Matic to play the ball in.

Yet Shaw's role in the goal was not enough to keep him on the pitch beyond half-time. Mourinho, who has been critical repeatedly of the left-back, decided to bring on Young for the second half.

Young provided the assist for the second goal, headed in by Matic, from what was United's only effort on goal in the second half.

Sanchez drops out - to little effect

Scott McTominay lost possession 19 times during the game, earning Mourinho's criticism

Mourinho's response to Tuesday's defeat was to make five changes - the most notable of which was to drop January signing Alexis Sanchez to the bench.

Paul Pogba was also left among the substitutes; a sign of how disappointed Mourinho has been with the £89m club-record signing of late.

The changes had limited impact. United's play, for long spells, was as pedestrian as it had been against Sevilla, and Mourinho declared himself unimpressed by the performance afterwards.

Brighton's decision to defend deep for much of the first half resulted in United spending long spells passing the ball sideways across the pitch, almost for the sake of it.

Scott McTominay, a midfielder who has been impressive since being promoted from the youth set-up, did not have a good night, with Mourinho critical of him for giving the ball away too often.

When the visitors adopted a more ambitious approach after half-time, United began to look very wobbly; had Locadia been more ruthless in front of goal, a difficult night could have become very awkward.

Jurgen Locadia has scored against Coventry and Swansea since his arrival in England, but was off target with this second-half header

Seagulls wonder what might have been

Brighton manager Chris Hughton's decision to leave top scorer Glenn Murray on the bench against Coventry in the fifth round was justified - it gave Locadia and Leonardo Ulloa valuable game time, and both scored.

At Old Trafford, Hughton's decision was harder to understand, and he might have been left wondering if resting Murray caused Brighton to miss their chance of a first FA Cup semi-final since 1983.

Only Manchester City's Sergio Aguero and Liverpool's Mohamed Salah have scored more Premier League goals in 2018 than the Cumbrian, who had to settle for a 14-minute cameo as a substitute against United.

The manager could argue that Premier League survival is the priority, but with his side on 34 points, they are surely already within reach of safety.

Brighton's 13-goal top scorer Glenn Murray appeared for the final 14 minutes

As it turned out, Brighton were more than prepared to have a go. An early willingness to defend deep gradually gave way to a more offensive approach; even before United scored, right-back Ezequiel Schelotto was keen to get forward, while centre-back Dunk tested Romero with a header from a corner.

In the second half, Brighton had 12 efforts at goal to United's one. Aside from Locadia's four chances, the visitors also very nearly equalised when Pascal Gross steered a clever inswinging shot just wide with the outside of the boot soon after the break, and the German midfielder was close twice more late on.

The first of those late chances was set up by Murray, whose introduction - sadly for Brighton - came too late to allow him to repeat his feat of rounds three and four, when he scored winners to take Hughton's side through.

"I was delighted with the performance," said Hughton. "The only difference were the moments in front of goal and the quality they can produce.

"Regards being a goal threat, I thought we had a lot around the box and we were as big a goal threat as they were. They had more possession which you would expect. We were always in the game."

Man of the match - Nemanja Matic (Man Utd)

The Serb midfielder ended with one assist and this goal - with Mourinho describing him as "an island of personality" while criticising the rest of United's players

Mourinho ends 11-year FA Cup wait - the key stats

Jose Mourinho has reached the FA Cup semi-final stage for the first time since 2007 when managing Chelsea.

Mourinho has won 15 of his 17 home FA Cup matches (D1 L1), winning all three with Manchester United by an aggregate score of 12-0.

Chris Hughton, meanwhile, has managed five away matches at Old Trafford in all competitions and lost all five without seeing his sides score a single goal.

Romelu Lukaku has scored 12 goals in his last 11 FA Cup appearances - the only match he failed to score in of those 11 games was against Man Utd for Everton in the semi-final in April 2016.

Lukaku has been directly involved in 14 goals in his 14 appearances in 2018 (10 goals, four assists).

Indeed, the Belgian striker has either scored or assisted in each of his last five appearances for Manchester United.

Nemanja Matic has both scored and assisted in a game for the first time since August 2014 for Chelsea against Everton.

What's next?

Manchester United's Premier League season resumes after the international break with a home game against Swansea on Saturday, 31 March (15:00 BST); Brighton host Leicester at the same time.