Having begun his tenure as England test coach with a bang, Brendon McCullum's methods have arguably never faced a bigger challenge.
In tandem with Ben Stokes, McCullum's approach - dubbed 'Bazball' - had won 11 of 13 tests leading into this year's Ashes series, as the pair were heralded for reinventing test cricket.
And while those claims largely bordered on hyperbole largely from the English media, the results were there to see.
Backing his players to favour aggressive cricket above all else, McCullum appeared to have unlocked England's full potential with the bat, notably seeing his side hammer a record 506/4 in a single day against Pakistan at the end of 2022.
But down 1-0 to Australia in the best of five series, England have all the work to do if they're to avoid going 2-0 down at Lord's, behind by more than 200 runs, with two full days still to play.
Only one side has ever come back from 2-0 down in the Ashes, all the way back in 1936/37 - and that was an Australian team containing Sir Donald Bradman.
That first defeat came at Birmingham's Edgbaston last week, as an aggressive declaration from Stokes on day one opened the door for Australia to stay in the game, and eventually win by two wickets.
Now, the shoe is on the other foot.
With Australia 130/2 in the second innings and ahead by 221 runs, it's likely England will be asked to chase a target in excess of 400, considerably higher than the Lord's record winning score of 344 set by the West Indies in 1984.
A record run chase won't phase England, though. Of those first 11 wins, seven came batting last - including a chase of 378 in a seven-wicket victory over India in Birmingham.
What's more, Australia will be without spinner Nathan Lyon, who picked up an injury in England's first innings.
However, up against an Australian attack led by the pace battery of captain Pat Cummins, Mitchell Starc and Josh Hazlewood at Lord's, England's aggression has been their undoing.
In the first innings at Lord's, in which England fell from 188/1 to 325 all out, six of the top seven batters all fell playing aggressive shots at a time when the game was there for the taking.
For former Blackcap turned England spin coach Jeetan Patel, though, the hosts won't change their approach, despite its shortcomings so far this series.
"We've always said we want to play an aggressive brand," said Patel. "It's not always going to come off - that's not a cop out, it's just reality.
"We want to keep changing momentum, we want to force swings in the game that come back our way, like you'd see in white ball cricket. We want to keep scoring, we want to keep pushing the pressure back on the opposition.
"It didn't come off today, but there's another opportunity in the fourth innings, and there's a lot more on it in the fourth innings when it's chasing down a score."
While it would be unfair to pinpoint England's aggressive approach for their current predicament, it certainly hasn't helped.
Across their first three innings of the series, England have batted for innings of 78 and 66 overs in Birmingham, and 76 overs at Lord's. Australia meanwhile have batted for totals of 116, 92 and 100 overs respectively.
England's innings being so short - due to their aggressive approach - has given their bowlers little time to recover, and made things easier for Australia's batters in a rinse-repeat cycle.
While England's bowlers have struggled to back up from innings to innings, Australia's haven't, and will likely be fresh again when the second innings comes around.
After the defeat in Birmingham, McCullum vowed England would go even harder at Australia at Lord's.
That approach hasn't gone down well, though, with former England captain David Gower suggesting lessons have not been learned.
"I want 'Bazball' to get smarter," he said. "I'm getting sick of people running down the pitch and missing it when they're playing well."
While derided by many, 'Bazball' isn't about playing aggressive cricket more than it's about playing without the fear of consequence.
Even if they were to go 2-0 down, they would still have confidence in winning the series 3-2, because of the environment created by McCullum and Stokes.
But for the first time under McCullum's leadership, this series has seen 'Bazball' in serious danger of backfiring.
