Ollie Pope crashed his maiden Test double hundred and Ben Duckett helped himself to 182 on a completely one-sided second day of England's Test against Ireland at Lord's.
Pope's 205 from 208 balls is the fastest Test double ever made in England, while Duckett missed out on becoming only the fifth man to make 200 in fewer than 200 balls.
With Joe Root helping himself to 56 at almost a run a ball, England pulverised the Ireland attack in perfect batting conditions.
England racked up 524-4 declared, passing 500 inside 80 overs, the second-fastest in Test history behind their own stunning 506-4 on the first day of the first Test against Pakistan in December.
Faced with an enormous deficit of 352, Ireland's primary target was not to suffer the indignity of defeat inside two days.
That became a real prospect when England debutant Josh Tongue took his first and second Test wickets - Peter Moor and Andrew Balbirnie - in his first over.
Tongue, 25, was also the bowler when James McCollum injured his right ankle trying to evade a bouncer, effectively leaving the Irish 25-3.
In a hostile spell, Tongue then had Paul Stirling caught down the leg side, but Harry Tector and Lorcan Tucker dragged Ireland to 97-3 at the close, still 255 behind.
Carnage in predictable mismatch
With England 152-1 overnight, 20 behind Ireland's first-innings 172, it seemed nailed on that the home side would pile on as many runs as they pleased.
Sure enough, carnage ensued. On a flat pitch under warm sun and against an inexperienced attack lacking any sort of cutting edge, England's batters gorged themselves.
This was Test cricket in name only, as England were able to add 372 runs at nearly seven an over with minimal effort. It was hard to not feel sympathy for the Irish, whose task of stopping the England juggernaut has proved beyond much stronger sides.
The mismatch continued when England took the ball thanks to Tongue's venomous spell of 3-27.
Moor was lbw to Tongue's first ball before Balbirnie cut behind. In Tongue's second over, there was the worrying sight of McCollum, swivelling to avoid a short ball, collapsing to the floor in obvious distress before being helped off the field and taken from the ground by ambulance.
Stirling at least steadied with Tector before a review detected a glove down the leg side and Tongue's viciousness continued when he struck Tucker on the helmet. Somehow, Tector had battled to 33 and Tucker to 21 when the mercy of the close came.
Pope and Duckett tuck into run feast
Pope and Duckett are two of the many success stories in this era of the England Test team - Pope since his elevation to number three last summer, Duckett after his recall to open the batting during the winter.
Duckett cut the first ball of the day for four, setting the pattern for the next two sessions. England scored 173 before lunch, then another 178 between lunch and tea.
Duckett cut and clipped the seamers, then swept and slog-swept the spin of Andy McBrine in his second Test hundred. In moving from his overnight 60 to 161 at lunch, the left-hander became the first batter since 1924 to score 100 runs before lunch in a Lord's Test.
He was on course for the fastest double hundred in a Test in this country before he inside-edged a drive at Graham Hume onto his own stumps, ending a stand of 252 with Pope.
The record instead went to Pope, who played gorgeous cover drives and hared between the wickets. His hundred partnership with Root, who was playing reverse-scoops as early as the 12th ball he faced, came from only 79 balls - England's third-quickest of all time.
When Root got to 52, he became only the second England batter after Alastair Cook to reach 11,000 Test runs.
He was bowled after tea, charging at McBrine, leaving Pope to go to 200 with a loft over the long-on boundary - his third six.
Pope was stumped next ball, prompting the declaration. England's overall run-rate of 6.34 is their highest ever in a home Test innings lasting more than 20 overs, and second-highest anywhere for an innings of at least 50 overs.
'I don't think we learned a great deal' - what they said
England batter Ben Duckett, speaking to Test Match Special: "Back garden as a kid you dream of moments like that. It really hasn't sunk in yet - it's been an incredible day. My family have been here so it was special to do it and have them here to watch it. It was fantastic to bat with Popey in that partnership."
Ireland spinner Andy McBrine, speaking to TMS: "The way Ben [Duckett] and Ollie [Pope] played took the sting out of the game. We have a lot of work to do over the next two days.
"We love playing Test cricket - it is what everyone wants to play. You could ask so many people who would love to be here. We will cherish every moment."
Former Ireland wicketkeeper Niall O'Brien on TMS: "It was difficult viewing. I give credit to England, they are ruthless - runs are hard to come by most of the time in Test cricket."
Former England captain Michael Vaughan on TMS: "England have been excellent - very professional. They have played the style of cricket I completely expected. With the bat in hand I knew they would try to score over six runs per over.
"I don't think we learned a great deal, even though it was fantastic from the batters. The Irish attack is poor."
