Match ends, Brighton and Hove Albion 0, Middlesbrough 2.
Middlesbrough secured only their second victory in 13 Championship games by beating play-off hopefuls Brighton.
Albert Adomah opened the scoring for Boro after 65 minutes, steering the ball home from inside the six-yard box.
Leonardo Ulloa missed the chance to equalise 12 minutes later, blazing over from the penalty spot after George Friend brought down Solly March.
And Danny Graham wrapped up the points late on with a low strike from 12 yards following a pass by Grant Leadbitter.
While victory was Boro's first away from home since January 11 at Blackpool, Brighton have slipped four points adrift of Reading in the final play-off spot.
The hosts should have opened the scoring early on, but midfielder David Lopez fired wastefully wide following a Will Buckley cross.
Tomasz Kuszczak was kept busy at the other end, though, making saves from Luke Williams, Lee Tomlin and Leadbitter.
And the pressure told in the second half as Seagulls skipper Gordon Greer allowed Graham to cross, with Adomah applying the finish.
Ulloa had the best chance to restore parity but was wasteful from the spot, allowing Graham to clinch the victory four minutes from time.
Brighton boss Oscar Garcia on fans booing at half-time: "I didn't hear it. I am first to the dressing room. It's normal. If they are not happy, they can do this.
"I can only say good things about the fans. They are clever fans; we have a mid-table budget and we are fighting for a high position.
"We're making mistakes at the back and we are being punished. The problem is we are not punishing the opposition ourselves and now these are the kind of things that are making the difference."
Middlesbrough manager Aitor Karanka: "It's my first season in English football and I'm very happy because everything is new to me.
"The potential is such that we have to work together to do the best. We have a good attitude and will be working to improve the squad in time.
"We created some good chances in the first half and didn't let Brighton play. We are playing in a very high tempo and deserved a slice of luck when Brighton missed their penalty."
- 38InceSubstituted forMarchat 73'minutes
- 21López MorenoSubstituted forLua Luaat 59'minutes
- 30BuckleySubstituted forForster-Caskeyat 33'minutes
- 9Rodríguez Sánchez
- 25Lua Lua
- 25OmeruoSubstituted forChalobahat 79'minutes
- 18WhiteheadBooked at 28mins
- 10TomlinSubstituted forButterfieldat 60'minutes
- 27AdomahSubstituted forLedesmaat 87'minutes
- Graham Scott
- Shots on Target
Second Half ends, Brighton and Hove Albion 0, Middlesbrough 2.
Attempt missed. Stephen Ward (Brighton and Hove Albion) left footed shot from the centre of the box is too high following a set piece situation.
Stephen Ward (Brighton and Hove Albion) wins a free kick in the attacking half.
Foul by József Varga (Middlesbrough).
Attempt saved. Jesse Lingard (Brighton and Hove Albion) right footed shot from outside the box is saved in the bottom right corner. Assisted by Jake Forster-Caskey.
Corner, Middlesbrough. Conceded by Bruno.
Attempt blocked. Jacob Butterfield (Middlesbrough) left footed shot from outside the box is blocked. Assisted by Nathaniel Chalobah.
Jesse Lingard (Brighton and Hove Albion) wins a free kick in the defensive half.
Foul by Grant Leadbitter (Middlesbrough).
Offside, Middlesbrough. Ben Gibson tries a through ball, but George Friend is caught offside.
Substitution, Middlesbrough. Emmanuel Jorge Ledesma replaces Albert Adomah.
Goal! Brighton and Hove Albion 0, Middlesbrough 2. Danny Graham (Middlesbrough) left footed shot from the centre of the box to the bottom right corner. Assisted by Grant Leadbitter.
Corner, Brighton and Hove Albion. Conceded by George Friend.
Kazenga Lua Lua (Brighton and Hove Albion) wins a free kick in the defensive half.
Foul by József Varga (Middlesbrough).
Attempt missed. Kazenga Lua Lua (Brighton and Hove Albion) right footed shot from the left side of the box misses to the left. Assisted by Stephen Ward.
Foul by Keith Andrews (Brighton and Hove Albion).
Danny Graham (Middlesbrough) wins a free kick in the attacking half.
Substitution, Middlesbrough. Nathaniel Chalobah replaces Kenneth Omeruo because of an injury.