Match ends, Middlesbrough 0, Brighton and Hove Albion 1.
Middlesbrough 0-1 Brighton & Hove Albion
Brighton manager Chris Hughton said he had "no hesitation" in picking match-winner Glenn Murray for the FA Cup win at Middlesbrough, despite the striker's arrest earlier in the week.
Murray and wife Stacy were arrested on suspicion of tax fraud on Tuesday.
Substitute Murray's goal in the 90th minute gave the Premier League side victory at The Riverside.
"He's been focused as normal and I had no hesitation in bringing him off the bench," said Hughton.
Murray struck when an attempt by Boro's George Friend to clear a cross from Markus Suttner hit Murray and rebounded past keeper Darren Randolph into the net.
"With all strikers, what you want is them to be in there, to anticipate. It was a very good cross in the first place and Glenn did what he does," Hughton added.
The hosts had impressed earlier on, with Adama Traore hitting the post before half time after a fingertip save from Tim Krul.
Baram Kayal went close for Brighton before Murray's dramatic intervention.
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He had gone close to reaching a cross inside the six-yard box a few minutes before his winning goal, his eighth of the season in all competitions, as the Premier League side finished strongly.
Jose Izquierdo had shot straight at Randolph from a tight angle, while Baram Kayal's long range shot was spilled by the Boro keeper with Jiri Skalak failing to convert the rebound.
But Boro were impressive, particularly in the first half when Traore struck the woodwork and Patrick Bamford saw his bicycle kick loop just over the bar onto the roof of the net.
League form more in mind
Both managers elected to leave their top scorers - Britt Assombalonga for Boro and Murray for Brighton - on the bench, with Chris Hughton making seven changes to the side that had lost 4-0 at home to Chelsea a week before.
Traore provided the best moments of the first half, with one elusive run down the right deserving much better than a poor finish from striker Ashley Fletcher that rolled nearer to the corner flag than the Brighton goal.
He was not as prominent after switching to the left wing in the second half, when Boro manager Tony Pulis brought on ex-England winger Stewart Downing and Assombalonga on in attacking double substitution.
Brighton improved markedly after the break, compared to their first half performance, with Murray's winner being his side's first goal since the 34-year-old Cumbrian striker had scored late on against Crystal Palace in the third round.
It will have proved to be a timely morale-booster for Brighton, who are just one point and two places above the relegation zone. Boro were unlucky at the end, but can now fully concentrate on moving up from eighth and into the Championship promotion race.
What the managers said
Boro manager Tony Pulis: "I'm disappointed for the players who have worked so hard again. But we've got to be more clinical in the final third.
"It's a fortuitous goal they've scored, it's a nightmare for us in respect the players don't deserve it, exactly the same as against Fulham.
"I just hope it's all the bad luck out of the way, because that's what it's been. You can't legislate for that."
Brighton manager Chris Hughton: "I'm really delighted with the application of the players.
"It was a tight game as we expected, but as the game opened up, we had the better opportunities to work the ball into the final third.
"As we got towards the end of the game, it looked like it was going to be a replay, which was certainly something both managers would not have wanted - so I'm really delighted to have got the winner."
- 4AyalaSubstituted forFryat 65'minutes
- 8ClaytonBooked at 44mins
- 10BraithwaiteSubstituted forDowningat 56'minutes
- 18FletcherSubstituted forAssombalongaat 56'minutes
- 6StephensSubstituted forPröpperat 45'minutesBooked at 68mins
- 7KayalBooked at 90mins
- 8SkalakSubstituted forIzquierdoat 61'minutesBooked at 70mins
- 9BaldockBooked at 61mins
- 10HemedSubstituted forMurrayat 72'minutes
- Anthony Taylor
- Shots on Target
Second Half ends, Middlesbrough 0, Brighton and Hove Albion 1.
Attempt missed. Jonny Howson (Middlesbrough) right footed shot from outside the box misses to the left. Assisted by Stewart Downing with a cross following a corner.
Corner, Middlesbrough. Conceded by Davy Pröpper.
Attempt blocked. Stewart Downing (Middlesbrough) left footed shot from outside the box is blocked.
Beram Kayal (Brighton and Hove Albion) is shown the yellow card.
Foul by Uwe Hünemeier (Brighton and Hove Albion).
Patrick Bamford (Middlesbrough) wins a free kick in the attacking half.
Attempt saved. Adama Traoré (Middlesbrough) right footed shot from the left side of the box is saved in the bottom left corner. Assisted by Patrick Bamford.
Goal! Middlesbrough 0, Brighton and Hove Albion 1. Glenn Murray (Brighton and Hove Albion) left footed shot from the centre of the box to the centre of the goal.
Hand ball by Connor Goldson (Brighton and Hove Albion).
Corner, Brighton and Hove Albion. Conceded by Dael Fry.
Attempt blocked. Beram Kayal (Brighton and Hove Albion) left footed shot from a difficult angle on the left is blocked.
Attempt missed. Anthony Knockaert (Brighton and Hove Albion) left footed shot from outside the box is high and wide to the left. Assisted by Markus Suttner.
Corner, Brighton and Hove Albion. Conceded by Dael Fry.
Attempt blocked. José Izquierdo (Brighton and Hove Albion) right footed shot from outside the box is blocked. Assisted by Markus Suttner.
Corner, Middlesbrough. Conceded by Beram Kayal.
Foul by Glenn Murray (Brighton and Hove Albion).
George Friend (Middlesbrough) wins a free kick in the defensive half.
Attempt saved. José Izquierdo (Brighton and Hove Albion) left footed shot from the right side of the box is saved in the centre of the goal. Assisted by Davy Pröpper.