Marcus Tavernier's early strike decided the Tees–Wear derby as Middlesbrough beat Sunderland 1-0 to move into the Championship play-off spots.
The 18-year-old winger was handed his first home start by Garry Monk, and he repaid the faith shown in him by meeting Martin Braithwaite's cross inside the first six minutes to break the deadlock.
Sunderland caretaker managers Robbie Stockdale and Billy McKinlay will have been encouraged by their side's response to the early setback, but they should have taken the lead prior to Tavernier's opener as Darren Randolph saved superbly from Lewis Grabban.
Randolph was then called upon to deny Didier Ndong and Billy Jones in the opening 15 minutes, but despite enjoying plenty of possession, the Black Cats rarely threatened a second-half equaliser.
It was the Black Cats who made the brighter start to the 131st league meeting between the sides, with the team without a manager denied superbly by Randolph inside the first four minutes.
Ndong picked the ball up in central midfield and unleashed a powerful shot that was parried by the former West Ham goalkeeper, but he made amends by getting back onto his feet to deny Grabban from point-blank range.
The hosts were spurred on by the double save and duly took the lead in their next attack. Stewart Downing was the architect as his fine pass into Braithwaite down the right allowed the Denmark forward to cross for Tavernier to guide the ball in at Robbin Ruiter's near post.
Tavernier - aged 18 years and 228 days - became the youngest league goalscorer for Middlesbrough this century behind Lee Cattermole and Adam Reach, but despite taking the lead it was Sunderland who remained on the front foot.
With Randolph calling for a cap to keep out the late-autumn sunshine, he managed to pull off two further saves in quick succession - first denying Cattermole's drive before brilliantly tipping Jones' header from Aiden McGeady's cross over the bar.
Sunderland continued to press in the second period, but it was Boro who came closest to stretching their lead as Ruiter twice denied Braithwaite after Britt Assombalonga had laid off Cyrus Christie's cross.
But it didn't prove costly as Middlesbrough held onto the three points to rise to fifth in the league, leaving Sunderland rooted to the bottom heading into the international break.
Man of the match - Darren Randolph
Randolph helped Boro to a third straight league win - a run in which he has now kept two clean sheets.
His early save from Lewis Grabban proved crucial, coming moments before Tavernier's match-winning strike, and the Republic of Ireland stopper had to be at his best once more to deny Billy Jones' header with the sun in his eyes.
Stewart Downing told Sky Sports after his team-mates heroic first-half display: "He's been brilliant since the first day he came in.
"The sun was in his eyes for the first chance but he still made a great save, and he made another two after it. We could've been 3-0 down. He fully deserves to be man of the match."
The managers
Garry Monk: "I expected that type of game. It was scrappy and the one bit of quality in terms of the goal means we deserved to win. We knew defensively we'd have to be on our mettle, so we're pleased to get the win."
Robbie Stockdale: "I haven't got a clue [if I'll be asked to take the Millwall match]. Our sole focus has been on this game and we made sure that this was our only concern really. You don't enjoy losing."
What next
Middlesbrough take on Leeds United at Elland Road on Sunday, November 19 - live on Sky Sports.
Meanwhile, Sunderland return from the international break with a home game against Millwall at the Stadium of Light on Saturday, November 18 and will likely be the first game for their new manager.