Substitute David Nugent’s stoppage-time header sent Aitor Karanka and the rest of the Riverside Stadium wild, securing a 1-0 win that moves Boro second, four points clear of visitors Hull.
It was, in truth, harsh on Hull after dominating large chunks of the game on Teesside - a devastating loss that was again borne out of an inability to convert.
“We certainly didn’t deserve that,” said Bruce. “Sometimes it is cruel, really cruel.
“If we’re being honest, we’ve had so many games over the last month, in particular, where we’ve been the best team, in my opinion, and had good opportunities, really good chances.
“Unfortunately, at the end we’ve been punished, which is cruel.
“My goalie hasn’t made a save, has he? I can’t remember theirs either, but the two big chances - (Ahmed) Elmohamady and Snoddy (Robert Snodgass) - we should be taking.
“We can’t keep missing chances like we’re missing and that’s been the same now for the last four or five weeks.
“We’ve created two really wonderful chances against Middlesbrough and haven’t been able to take it.”
Karanka enjoyed the “perfect” end to a turbulent week, with his return to the Middlesbrough dugout bringing with it a last-gasp victory against one of their main rivals for automatic promotion spot.
The former Real Madrid assistant manager’s days on Teesside had looked numbered when he walked out last Friday following a stormy meeting with his players.
Unable to smooth over the bust-up, Karanka watched Sunday’s defeat at struggling Charlton from afar, yet he surprisingly returned to his role as head coach and on Friday helped get their Championship promotion challenge back on track.
“I think it has been the best way to finish the day,” said Karanka. “The day, the week, everything - I couldn’t have imagined to finish the game in that way.
“I told the players before the game that it was going to be a really emotional game because of a lot of rumours, a lot of things had happened.
“I told them that it would be a really emotional game and we can’t forget that we’ve played against one of the best teams in the league.
“Hull were last season Premier League players (with) a Premier League manager, so for that reason it has been a perfect day for us.
“I said yesterday in the press that today was a good day to show everybody how big this club is, how great this crowd is and how good these players are when they play in the way that we have to play.
“For that reason I told them after the game, and I want to say to everybody, just one thing today: thanks.”