Oli McBurnie sent Tigers' fans into delirium with a 95th-minute goal at Wembley just as the match looked like it was going to extra time.
It was an easy take after Middlesbrough keeper Sol Bryn parried a cross into McBurnie's path and the striker tapped it home from inside the box.
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The Teesside club hunted for a last-gasp equaliser but failed to get a shot on target the whole match.
"It was tough out there with the heat and Middlesbrough are a top, top team," McBurnie told Sky Sports.
"We knew we were going to be right up against it, but we felt we'd have one chance and it was written for me to get it. I didn't think it would be so late on, but what a feeling."
Hull's victory is estimated to be worth in excess of nine figures due to broadcast money paid to top-tier sides and extra commercial revenue.
Coventry and Ipswich are the other clubs going up to the Premier League after securing automatic promotion.
Hull City were last in the Premier League nine years ago and rejoin football's elite after finishing sixth in the table and beating Millwall in the semi-final.
They have won promotion in all three second-tier play-off finals they've competed in, all by 1-0, previously doing so against Sheffield Wednesday in 2016 and Bristol City in 2008.
It's a remarkable turnaround for the East Yorkshire club, who last season avoided relegation to League One on goal difference.
The run-up to Saturday's game was mired in controversy after Southampton's "spygate" affair saw them kicked out of the big-money showdown and replaced by Middlesbrough.
The south coast club admitted spying on several teams this season, including a Middlesbrough training session days before their semi-final play-off - which Saints ultimately won.
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Southampton said the punishment was grossly disproportionate but the English Football League (EFL) rejected their appeal.
Hull had planned legal action if they were beaten by Middlesbrough instead of their original opponents.
It comes as the Democratic Republic of Congo's football team and staff have been told to isolate before travelling to the US for the World Cup.
Two Ugandans - a male driver who transported a patient who was the country's first confirmed Ebola case and a female health worker who treated him - are among the new cases, the Ugandan health ministry said in a statement on Saturday.
Both have since tested positive and are receiving treatment after being identified among known contacts, the ministry said.
They were exposed to a 59-year-old Congolese man, who was admitted to a hospital in Kampala on 11 May and died three days later.
The third case was a Congolese woman who entered the country from the Democratic Republic of Congo (DRC), "presenting with mild abdominal symptoms".
She travelled from Arua, close to the border, to Entebbe before seeking care at a private hospital in the capital Kampala, where she improved and returned to the central African country four days later.
The patient later tested positive for Ebola after a follow-up prompted by a tip-off from a pilot involved in transporting her.
All identified contacts linked to the confirmed cases are being closely monitored, the ministry said, urging the public to remain vigilant and report suspected symptoms.
Meanwhile the entire Congolese delegation to the football World Cup must isolate and maintain a bubble for 21 days or risk being denied entry to the US.
The team is currently training in Belgium.
Andrew Giuliani, executive director of the White House Task Force for the World Cup told ESPN: "We've made it very clear to the Congo government as well, that they need to maintain that bubble or they risk not being able to travel to the United States. We cannot be any clearer."
Their first match is against Portugal on 17 June in Houston followed by one against Colombia in Guadalajara in Mexico on 23 June.
All of the team's players are based outside DR Congo.
The World Health Organisation (WHO) has declared the outbreak of the rare Bundibugyo strain a public health emergency of international concern, and said the risk of a national epidemic in the DRC is "very high".
DRC, the centre of the outbreak, has nearly 750 suspected cases and 177 suspected deaths from the illness.
The country is particularly vulnerable because of late detection, the absence of a vaccine or virus-specific therapeutics, widespread armed violence and high mobility among the population, the organisation said.
The WHO said Ugandan authorities have stepped up contact tracing to contain the spread.
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In a post on X on Saturday morning, the WHO said screening has been boosted at major points of entry to Uganda, as well as health checks at Entebbe airport.
It said Ugandan health authorities were carrying out "enhanced disease surveillance, contact tracing and community engagement" in what it referred to as "high-risk districts".
A 71-year-old suffered a head injury after "several masked individuals broke into the house" in Nyon at around 8.30am on Tuesday, forcing another family member to open a safe, local police said in a statement.
According to reports, including from the Swiss tabloid, Blick, the injured party was Mr Prost, and it was his son who was forced to open the safe.
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"The perpetrators entered the residence while the occupants were present, threatened them, and forced one family member to open a safe before fleeing with the stolen goods," according to the public prosecutor's office.
What was stolen is "currently being assessed".
Police "immediately deployed a large-scale search operation and notified the public prosecutor's office, which opened a criminal investigation".
"The investigation is ongoing to identify and apprehend the perpetrators," the statement said.
No arrests have been made, police said, adding that officers are working out what was stolen.
As well as the Vaud police, a host of other agencies were involved, including regional Swiss and French police, science officers, customs investigators, and a psychological support team for the family.
Blick said Prost was "visibly shaken by this brutal intrusion" and that he's left the home beside Lake Geneva.
The Frenchman, known as 'Le Professeur', won four F1 world championships between 1985 and 1993, sharing a legendary rivalry with Brazilian driver Ayrton Senna.
In the footage, Mr Ben-Gvir, a member of the far-right party Otzma Yehudit (Jewish Power), can be seen waving a large Israeli flag over detainees who appear to have their hands tied behind their back.
He can also be seen taunting a kneeling detainee whose wrists are bound, yelling "Am Yisrael Chai", which is Hebrew for "the nation of Israel lives".
Another clip shows detainees with their foreheads on the floor as the Israeli national anthem plays.
In a post on X on Saturday, French foreign minister, Jean-Noël Barrot, said: "As of today, Itamar Ben-Gvir is banned from entering French territory.
"This decision follows his unspeakable actions toward French and European citizens who were passengers on the Global Sumud Flotilla.
"We cannot tolerate that French nationals can be threatened, intimidated or brutalised in this way - all the more so by a public official."
He was also critical of flotilla activists attempting to breach Israel's naval blockade of Gaza and added: "We disapprove of this flotilla's approach, which produces no useful effect and places an additional burden on diplomatic and consular services".
The flotilla of 50 boats, carrying about 430 people, was intercepted in international waters some 250 miles (400 km) off the coast of Israel.
Detained activists accused Israeli forces of mistreatment, describing beatings, tasers, and attack dogs.
World leaders - including coalition partner and Israeli Prime Minister Benjamin Netanyahu - condemned Mr Ben-Gvir's on-camera treatment of the detainees.
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Poland also announced a five-year ban on Mr Ben-Gvir on Thursday.
"In the democratic world we do not abuse and gloat over people in custody," Polish foreign minister Radek Sikorski said.
Dr Margaret Connolly, sister of Ireland's President Catherine Connolly, was one of the detainees to arrive at Dublin Airport on Saturday.
She was among the first wave of detainees after Israeli authorities intercepted the flotilla on Monday.
Detainees were then taken to Israel before being deported to Turkey on Thursday.
Dr Connolly said Israeli authorities "wanted us to suffer".
"None of them could look us in the eye. What a dehumanising thing to do to men and women aged 22 up to 75," she said.
Other detainees returning to Dublin described their poor treatment, and recounted being beaten, having guns pointed at them and being "tortured".
Alan Milburn is due to publish an interim report next week that examines why almost one million 16 to 24-year-olds are not in employment, education or training (NEET).
It will conclude that a "rising tide of mental ill health, anxiety, depression and neurodiversity" is a big factor in this economic inactivity.
Speaking to The Times, Mr Milburn rejected claims that young people are "snowflakes" - and said the country is at risk "of just writing a whole generation off".
According to the report, the rise of smartphones and social media has led to a "bedroom generation" that suffers from poorer sleep and lower levels of concentration.
"Every one of a group of ten 12 and 13-year-olds told us they went to bed between midnight and 3am because they were scrolling on their phone," it will warn.
The report will describe young people as different - and not worse, lazier or less intelligent than their peers in other age groups.
"They have grown up in a digital world that has rewired how they communicate, form relationships and manage stress," it will say. "They have fewer experiences of workplaces, and they present with higher levels of anxiety and depression."
COVID is also thought to have played a factor, as many 16 to 24-year-olds would have been in high school or college during lockdown closures.
Mr Milburn believes the UK's one million NEETs could plug labour shortages in the British economy, as long as employers are willing to make accommodations for them.
Speaking to the newspaper, he went on to warn that welfare reforms will be a "necessity" to help younger generations enter the world of work.
Figures from the Office for National Statistics suggest youth unemployment reached 16.2% in the three months to March - the highest level in 11 years.
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A report published earlier this week also identified social media as a driver of a so-called quitting culture among this age group.
The research, based on conversations with 400 young people, found some enjoyed "the dopamine hit of a new job but then get bored very quickly and want to move on".
Authors also warned that many students don't believe that school adequately prepares them for life or work - with secondary years dominated by exam pressure, and a focus on university education rather than alternative routes.