Lewis Koumas scored four minutes into his Hull debut as they moved within five points of the Championship summit after a 1-0 win at struggling Blackburn.
The 20-year-old, signed on loan from Liverpool on Friday, was introduced as a 77th-minute substitute and made an immediate impression, clinically slotting home the winner with nine minutes remaining.
Rovers appealed in vain for an offside flag that never came but the move that set up Koumas represented the first moment of quality in a game neither side really did enough to win.
However, Sergej Jakirovic's team were resolute in the face of Blackburn's pressure in the second half and are up to third after a fourth successive victory.
It was a punishing afternoon for Blackburn, who were made to pay for failing to convert two second-half headed chances for Yuki Ohashi and Mathias Jorgensen and they are three points from safety.
Regan Slater went close to a 15th-minute opener after stealing possession and let fly from 15 yards with a low drive Balazs Toth saved and Rovers scrambled clear.
Rovers weathered early pressure and almost nudged ahead when space opened up in the 33rd minute for Ryan Alebiosu to cut infield but Ivor Pandur made a flying save to palm behind his left-footed curler.
From the resulting corner, Hull cleared and Alebiosu let the ball bounce, allowing Liam Millar to nip in and race goalwards but the defender got a touch on his shot and the deflected effort was repelled by Toth.
The Tigers were furious moments later when Todd Cantwell escaped with a booking for appearing to react to Oli McBurnie's heavy challenge, with the striker in particular making his feelings known.
Rovers were much better in the second half and created two chances on the hour to get the vital breakthrough.
First, Ryoya Morishita's deep cross from the right found Ohashi who drifted in at the far post but Pandur foiled the forward.
A minute later, they passed up a better chance when Jorgensen planted his header over from five yards after meeting Connor O'Riordan's cross.
Rovers nearly paid the ultimate price for that profligacy in the 68th minute when Yu Hirakawa's header across the box was only cleared as far as the onrushing Kieran Dowell but he lashed well over.
There was no escape in the 81st minute as Hull scored what could be a crucial goal at both ends when Amir Hadziahmetovic fed Kyle Joseph, whose clever first-time pass found Koumas, and he took a touch before firing under Toth to send the away end delirious.
Although Joseph was denied by Toth when clean through in the 88th minute, Hull secured what felt like a vital victory.
Blackburn's Valerien Ismael:
"I don't know why it's so complicated. It's not about the performance today, not about the desire, the mentality.
"What we have to complain about is we have to take our chances. At some point you have to take the chance. When you dominate the game like this, you are on the front foot on the top of your subject, you have to get the reward and to make sure you score the goal.
"All of a sudden in the second half, from nothing, we concede that goal. After that, late in the game, it's tough for the players because they are trying to give everything. We see completely another Rovers than we saw maybe a couple of weeks ago due to the injuries we had.
"The power is there, the willingness is there, so any reason why we're not winning at home, why it's so complicated this season? So now we have to keep that performance, to make sure that when we get the chance, we take our chance."
Hull's Sergej Jakirovic:
"He's Liverpool school, he's a Liverpool winger, when I saw him in the summer, he was my wish but he chose Birmingham.
"This is normal, in that situation you can choose a club in a better situation. But there is no ego from my side, I respect every player's decision but now when we had the opportunity to take him I said immediately we must take him.
"He's so young, such big potential with a lot of experience in this league and especially in the January transfer period, there is no adaptation and I think he helps us.
"I think he can help us a lot. He's a young player but he played in Stoke, now in Birmingham and this is the reason we took him immediately. I think he can improve this group a lot."
