It was a game Boro simply had to win to stand any chance of pulling off a great escape.
There was a tremendous atmosphere before the kick-off at the sell-out Riverside Stadium with both sets of fans realising the importance of the game.
Hull could also now be involved in a desperate scramble to avoid the drop so an action-packed game was inevitable.
Middlesbrough named an attacking line-up with record club buy Afonso Alves and loan signing Marlon King in attack.
Turkey international Tuncay game the home side a tremendous start with a goal in the third minute. Alves' shot from the edge of the penalty area was saved by Tigers goalkeeper Matt Duke but Tuncay darted forward and fired the rebound into the net.
Middlesbrough fans were jubilant but the strong Hull contingent had something to celebrate six minutes later.
Former Middlesbrough forward Nick Barmby sent over a right-wing cross which Manucho headed powerfully past Boro keeper Brad Jones.
Hull's quick response once again demonstrated Middlesbrough's defensive weakness with crosses.
Shortly afterwards Jones bravely denied Craig Fagan. The ball ran loose and Manucho shot wide from an acute angle.
Middlesbrough restored their lead through Matthew Bates after 29 minutes, his first Premier League goal.
A recognised defender who was operating in midfield, Bates darted forward to shoot past Duke from the edge of the six-yard box. Hull manager Phil Brown would have been disappointed with the marking from Tony McMahon's right-wing corner.
Middlesbrough were the more threatening side while at the other end Hull skipper Ian Ashbee was off target with a wild shot.
Middlesbrough central defender Robert Huth resumed the second half with his head bandaged after being injured just before the break.
Huth did his best to get his name on the scoresheet when he headed Stewart Downing's free-kick past the far post.
Hull battled hard to pull the game round but they came up against a defiant Middlesbrough defence.
In the final minute Boro grabbed a third goal thanks to King. After Jeremie Aliadiere had challenged Tigers substitute George Boateng, the ball ran loose for King to pounce and shoot past Duke.