The 19-year-old defender was a shock call-up after being limited to youth and reserve team football and no doubt the majority of Boro fans had never heard of the youth international.
Yet in the 32nd minute they were cheering the Wetherby-born teenager for giving Boro the lead with his first goal in senior football.
Hines moved forward, took a lucky break when a ball bounced off a defender and, from just inside the penalty area, shot past Boaz Myhill.
Middlesbrough had the balance of play and Mark Viduka twice went close. A downward header went over the bar and then he shot just past the far post.
Immediately after the break Viduka put Middlesbrough further ahead after a James Morrison shot had hit a post.
Middlesbrough striker Yakubu shot against the bar but immediately afterwards was on target from the penalty spot after Stewart Downing was brought down in the box by Stephen McPhee.
The game looked all over when Yakubu nonchalantly beat Myhill to boost his penalty-king reputation.
Hull, however, had other ideas. Roared on by a vociferous 3,000 following, the Tigers staged a stirring comeback.
Andy Dawson scored with a header and then Jon Parkin reduced the arrears further from the penalty spot after Abel Xavier had brought down Nicky Forster just inside the box.
Dawson set the tone for a thrilling finale when he pulled another goal back for Hull with a brilliant free-kick.
Hull deserved tremendous credit for refusing to give up the ghost when it looked as though Middlesbrough were set for a comfortable win at one stage.
Hull manager Phil Brown roared on his team from the technical area as tension mounted, while his Boro counterpart Gareth Southgate was relieved at the final whistle.