Match ends, Newport County 2, Leicester City 1.
Newport County dumped 2016 Premier League champions Leicester City out of the FA Cup third round at a raucous Rodney Parade thanks to Padraig Amond's late penalty.
Jamille Matt's perfectly placed header after a pulsating run and cross from Robbie Willmott gave the Exiles the advantage against a side 74 places above them in the football leagues.
Marc Albrighton hit the crossbar and Newport goalkeeper Joe Day produced a string of saves before Rachid Ghezzai smashed the Foxes level.
However, Amond's 85th-minute penalty after Albrighton's handball sent the crowd into raptures as Newport produced one of the greatest results in their history.
It is not an exaggeration to say Newport and Leicester are at completely opposite ends of the footballing scale. The year Leicester stunned the world under Claudio Ranieri to win the Premier League, Newport finished 22nd in League Two.
The enormity of the achievement was shown in scenes of jubilation at full-time as Newport's players sank to their knees and punched the air in delight while their fans went wild.
Manager Michael Flynn hugged assistant Wayne Hatswell and his mentor, veteran manager Lennie Lawrence to celebrate a seismic result for the city.
Newport supporters could barely contain their glee, but did interrupt their celebrations to question BBC Match of the Day presenter Gary Lineker - a Leicester fan - with cries of "Gary, what's the score?".
Rodney Parade rocking
The old Newport County went bust in 1989 and rose back through the wilderness to return to the Football League in 2013. They had not beaten a top-flight side in the FA Cup since 1964.
Flynn has overseen an extraordinary renaissance for the club, who were 11 points adrift of League Two safety with only 12 games remaining when he took charge in 2017. He kept County up and they have since punched well above their weight.
Newport, who took the lead against Tottenham in the fourth round last year, shocked Leicester after 10 minutes when Robbie Willmott's superb run and cross provided the perfect ammunition for Matt to rise above Wes Morgan and head home his 14th goal of the season.
Leicester should have been in front but Joe Day twice denied Ghezzal, and all of a sudden they - and a sold-out Rodney Parade - were rocking.
Leicester goalkeeper Danny Ward did well to block Matty Dolan's shot as Newport grew in confidence, Flynn conducting his players through a cacophony of noise.
Matt missed a clear chance to double Newport's lead when Ward smothered after Amond's clever centre.
Newport punish wasteful Leicester
Although Leicester boss Claude Puel made seven changes to his side - Jamie Vardy was left out and James Maddison named on the bench - he still selected five Premier League winners in the starting XI.
Leicester created several chances and should have earned at least parity by half-time, but careless finishing and last-gasp Newport defending denied them.
Albrighton headed just wide when hitting the target seemed a certainty, Shinji Okazaki's shot was brilliantly stopped by Mickey Demetriou, and Kelechi Iheanacho headed straight at Day.
Albrighton's whipped effort clipped the crossbar, Iheanacho found space yet fired across goal, and Fraser Franks did superbly to block half-time substitute Maddison's shot.
Just as Leicester seemed to be running out of ideas, Ghezzal smashed them level after Day kept out Iheanacho's header.
But Albrighton inexplicably handled in the box to gift Amond the chance to coolly send Ward the wrong way from the spot.
'My voice has gone' - what they said
Newport manager Michael Flynn told BBC Sport: "It was unbelievable. My voice has gone.
"I'm so proud of the players. They were excellent from start to finish - the amount of work they did off the ball and the chances we created as well.
"Let's not say that we just hung on - we created quite a few chances. And my assistant Wayne Hatswell said that Gary Lineker owes him a pint because he keeps going on about the own goal he scored!"
Leicester manager Claude Puel told BBC Sport: "Congratulations and well done to this team. They believed in themselves and created the upset.
"It is a big disappoint for us. It is difficult to accept.
"We had lots of opportunities without finding a clinical edge.
"We thought we did the most difficult thing to come back and then conceded a penalty. It was a typical cup game with the conditions.
"We had an experienced team to manage this game. We had lots of experience and a good team on the pitch."
Scoring for fun in the cup - best of the stats
- Newport's victory was their first FA Cup win against a side from the top tier of English football since beating Sheffield Wednesday in the third round in 1963-64.
- Leicester have been eliminated from the FA Cup by a side in the fourth tier of English football or lower for the first time since non-league Harlow Town knocked them out in a third-round replay in 1979-80.
- Leicester have lost back-to-back games in all competitions against fourth-tier opposition (Shrewsbury Town and Newport County) - as many defeats as in their previous 34 matches against such opponents (W31 D1 L2).
- This is the first time two top-flight sides have been knocked out of the FA Cup by teams from the fourth tier or below on the same day since 7 January 1989, when Middlesbrough were beaten by Grimsby and Coventry by Sutton United.
- Newport have scored 16 headed goals in all competitions this season. Of sides currently in the top four tiers of English football, only Aston Villa have scored more (19).
- Jamille Matt has scored on five of his six starts in the FA Cup since his first in November 2016.
- 21Hornby-ForbesSubstituted forPipeat 67'minutes
- 8DolanSubstituted forO'Brienat 86'minutes
- 11MattSubstituted forBakinsonat 77'minutes
- 2SimpsonSubstituted forGrayat 60'minutes
- 22JamesSubstituted forKingat 72'minutes
- 20OkazakiBooked at 45minsSubstituted forMaddisonat 45'minutes
- 14Ricardo Pereira
- Chris Kavanagh
- Shots on Target
Second Half ends, Newport County 2, Leicester City 1.
Attempt missed. James Maddison (Leicester City) right footed shot from outside the box misses to the right. Assisted by Rachid Ghezzal.
Attempt saved. Andy King (Leicester City) right footed shot from the centre of the box is saved in the centre of the goal. Assisted by Hamza Choudhury.
Corner, Newport County. Conceded by Jonny Evans.
Attempt blocked. Antoine Semenyo (Newport County) left footed shot from the left side of the box is blocked. Assisted by Padraig Amond.
Corner, Leicester City. Conceded by Fraser Franks.
Substitution, Newport County. Mark O'Brien replaces Matthew Dolan.
Goal! Newport County 2, Leicester City 1. Padraig Amond (Newport County) converts the penalty with a right footed shot to the centre of the goal.
Penalty conceded by Marc Albrighton (Leicester City) with a hand ball in the penalty area.
Attempt blocked. Demarai Gray (Leicester City) right footed shot from outside the box is blocked. Assisted by Christian Fuchs.
James Maddison (Leicester City) wins a free kick in the defensive half.
Foul by Matthew Dolan (Newport County).
Goal! Newport County 1, Leicester City 1. Rachid Ghezzal (Leicester City) left footed shot from outside the box to the top left corner.
Attempt saved. James Maddison (Leicester City) right footed shot from the centre of the box is saved in the centre of the goal. Assisted by Kelechi Iheanacho with a headed pass.
Attempt missed. James Maddison (Leicester City) right footed shot from the centre of the box misses to the right. Assisted by Marc Albrighton.
Attempt blocked. Rachid Ghezzal (Leicester City) left footed shot from the centre of the box is blocked.
Corner, Leicester City. Conceded by Fraser Franks.
Substitution, Newport County. Tyreeq Bakinson replaces Jamille Matt.
Marc Albrighton (Leicester City) wins a free kick in the defensive half.