Jacksonville Jaguars 34 Buffalo Bills 31

Wembley welcomed the millionth fan to watch an NFL International Series game through the gates of the national stadium for Sunday's Bills at Jaguars clash. He was wearing the colours of the Jacksonville Jaguars and must have gone home a happy man..and a relieved one.

The Jaguars, who were playing a home game in London for the third successive season and announced on Thursday that they will extend their residency until 2020 at the earliest, won in the UK for the first time, but they did it the hard way in a ridiculously exciting game.

They built what seemed an unassailable 27-3 lead in an explosive six-minute spell in the second quarter in which they scored four touchdowns. Two came within nine seconds as EJ Manuel, the Buffalo Bills backup quarterback, fumbled and them had a pass intercepted, both only yards from his own endzone, giving the Jaguars their first two defensive touchdowns of the season.

Yet somehow the Bills hit back to take a 31-27 lead late in the fourth quarter when a pass by young Jaguars quarterback Blake Bortles was intercepted and returned for a touchdown by Buffalo safety Corey Graham. But Bortles recovered to throw the game-winning touchdown to Allen Hurns and afterwards Jaguars head coach Gus Bradley praised his second-year field general.

“I thought he showed great poise, the whole team did offensively,” Bradley said. “I'm very pleased with what took place. We've got to look at some things, but there's a lot of good things about our team, the grit, the resiliency. All year we have fought back but not had the results to show for it.”

Jaguars owner Shahid Khan must have thought he had an exciting Saturday afternoon when the Fulham team he also owns came from 2-0 down to beat Reading 4-2 at Craven Cottage, but it had nothing on this. And that millionth fan, who was presented with a guarantee of tickets to all future Jaguars games here, and must have been wondering whether he would ever see them win, can now wear his shirt with pride.

Both of the Jaguars' previous Wembley appearances had ended in heavy defeats, 42-10 by the San Francisco 49ers in 2013 and 31-17 by the Dallas Cowboys last year, despite Tony Romo, the Cowboys quarterback, playing with a broken back. This result and performance, Bradley agreed, could be important for their prospects of building their UK fanbase in the long term. “The guys felt [the crowd's support] throughout the game,” he said. “It's important to get a win and to get it here in front of our fans across the pond is awesome.”

Although their won-post record for the season is still 2-5, the Jaguars will go home happy. “It will make the eight and a half hours back a lot easier,” Bortles said. “It was a good team win. Our defence kept us in it. Being ahead is something new to us so we're still figuring out how to keep the pedal to the metal and put teams away.”

The injury-hit Bills, however, will have to do their best to salvage what positives they can from their first visit to the UK. “A devastating loss, to say the least,” their head coach Rex Ryan said. “We found a way to come back, not only come back but to come all the way back and take the lead. It just kills you right now but I'm proud of the effort. This team will stick together, there's no question about that.”

After a stunning display of precision and artistry from the Ohio State University Marching Band, the early stages of the game predictably fell short in both those areas.

Without injured first choice quarterback Tyrod Taylor and wide receivers Percy Harvin and Sammy Watkins, the Bills' obvious strategy would have been to hand star running back LeSean McCoy have the ball as much as possible, but too many failed passing plays from Manuel meant that they had to settle for a field goal.

But in Bortles, the third overall pick in the 2014 draft, Jacksonville have a talented and improving quarterback, and his passes were finding their targets, even against Ryan's noted defensive schemes. 55 seconds into the second quarter, his ten-yard pass found wide receiver Allen Robinson for the game's first touchdown.

While Bortles thrived, Manuel imploded. On his next possession he was sacked by cornerback Aaron Colvin and ball jumped out of his grasp. It was recovered by defensive end Chris Clemons, who had the simple task of carrying it all of six yards to the endzone.

14-3, and Manuel's nightmare had just begun. Nine seconds later his next pass towards Robert Woods was woefully underthrown, and linebacker Telvin Smith picked it off and ran it 26 yards back for another six points.

Another intercepted pass, this time 36 yards out by former Bill Paul Posluszny, led to another score as Yeldon ran in three plays later. The only bright spot for Buffalo was that the extra point was missed, putting them 27-3 in arrears.

At that point, you could not see the Bills daring to let Manuel throw again, especially given the post-match suggestion that he had had difficulty hearing coaching instructions in his helmet headset. But Ryan said: “I thought he had too good a week on the practice field to end it like that. I thought he needed a chance to rebound.”

And he did, throwing four consecutive completed passes, three to Woods, the last 16 yards for a touchdown. A field goal reduced the arrears to 27-13 – a difference of two touchdowns - and a heroic four-down stand on their own one-yard line gave them hope. At that point, the Jaguars' decision to try to score a touchdown on fourth down rather than kick the field goal that would have put them 17 points ahead seemed unimportant, even when another Buffalo field goal made it 27-16.

“If it doesn't work out we still have them backed up,” Bradley said. “It's our mentality to go for it. I don't know if that was the momentum-changer.”

Something certainly was, and after another field goal, Manuel hurled a spectacular 58-yard touchdown pass to receiver Marcus Easley to make it 27-22. A successful two-point conversion brought them to within a field goal of parity at 27-24, and they were ahead when Bortles, under pressure, threw a looping pass that was intercepted and returned 40 yards for a touchdown by Graham.

That might have crushed most teams, especially if they had won only one previous game all season. But Bortles recovered and restored the Jaguars' lead with a pass to wide receiver Hurns, who somersaulted acrobatically into the endzone. This time there was no way back for the Bills. “If we had lost this it would have been hard,” Smith said. “I know a lot of people would have criticised us and the coaches, but for the team to fight, not only for us but for the coaches also, it's just great.”