Ramirez was influential as Boro recorded their third victory of the season over a limited Hull side on a bitterly-cold night at the Riverside.
He scored the only goal of the game against his former employers, as Aitor Karanka’s men moved up to 13th in the table, giving themselves breathing space away from the looming relegation zone.
Hull, who had several injuries and suspensions following their League Cup excursions last week, held their own for just under an hour, before Ramirez found himself unmarked from a corner and broke the deadlock with a back-post header.
On the balance of play it was deserved, and despite not creating too many clear-cut chances, the hosts dominated possession while looking secure at the back for most of the game.
Once again Karanka’s side looked solid in the middle of the park, as the midfield trio Adam Forshaw, Marten De Roon and Adam Clayton recycled possession well all night.
The Boro boss did make one change from the side which drew with Leicester last time out as Viktor Fischer replaced Adama Traore, who dropped to the bench.
Hull limited upfront
After playing through extra-time and penalties against Newcastle United in the cup, Hull manager Mike Phelan made two changes from the side which drew 1-1 with West Brom in the Tigers' last league outing.
Adama Diomande came in for the suspended Dieumerci Mbokani upfront and the visitor’s lack of firepower upfront was clear to see. Meanwhile Andrew Robertson replaced Josh Tymon at left back.
It was down the visitors left where Boro calved out the first chance of the game on six minutes, when the lively Ramirez knocked the ball inside to De Roon. The Dutch midfielder then set Negredo, however the striker scooped the ball over the crossbar.
Ramirez was Boro’s catalyst again minutes later when the Uruguayan playmaker cut inside from the right-hand-side and tested Hull 'keeper David Marshall with a skimming effort.
Boro struggle to break the opposition down
The hosts continued to see most the ball but lacked the zest and verve to break down a well organised City side.
Another shot from Forshaw forced Marshall to make another save from distance, as Boro huffed and puffed to find a clearer route to goal.
On the half hour mark they finally found the net when Ramirez, who continued to look the greatest threat, crossed for Negredo, who knocked the ball down into Fischer’s path. The Danish international managed to bundle the ball home, however he had wondered into an offside position and the goal was chalked off.
Hull had offered little going forward but almost made a decisive break through when Diomande was released through on goal. However, he was denied by an excellent slide tackle by Gibson, who did remarkably well not to concede a penalty.
Even so, Boro picked up where they left off after the break and quickly began to pile on the pressure by winning an array of corner’s early in the second half.
Ramirez proves the difference
Eventually they made one count on 59 minutes when Fischer’s flat in-swinging corner travelled all the way to the far post where it was nodded in by Ramirez, who sent the Riverside into raptures.
Hull’s response was to bring on Tom Huddlestone and Jarrod Bowen but by that stage Boro were content to play on the counter attack.
Ramirez suffered a knock in the closing stages and was forced off with three minutes to go, before being replaced by Stewart Downing.
There was almost a late twist in the tale when Diomande forced a late save from Victor Valdes, before Michael Dawson flicked a header wide from the resulting corner but 1-0 it stayed.