Stuart Lancaster says Leinster need to have saved their best until last for Saturday's Champions Cup final.
But the Blues senior coach admits today could be D-Day for Tadhg Furlong and James Lowe's hopes of making the La Rochelle showdown as they try to recover from knocks suffered in the semi-final.
Leinster will have a big training session today before taking tomorrow off and flying to Marseille on Thursday, and their doubtful Ireland stars need to show they are ready for action.
That's certainly the case for Furlong, despite his importance to his side's scrum.
"He’s got to be right," admitted Lancaster. "It's very hard for a tighthead prop to go into a scrum if you're not right.
"If not it will compromise our chances, never mind Tadhg’s chances of doing well."
Lancaster says it's the defeats that stay with him more than the wins and so last year's last four defeat to La Rochelle still hurts.
As long as Furlong is fit, Leinster will be much stronger in terms of personnel than they were - but the ex-England boss insists that both sides have evolved for the better since then.
"Obviously it's important to play your best game in the final," said Lancaster.
"You saw in the World Cup in 2019, South Africa played their best game in the final and won the final.
"Yeah, you can talk about it but until the actual final starts itself, it's only then when you truly know where your group is.
"You've got to prepare for every eventuality.
"You're always hoping for the 10/10, and it never plays out that way, but to win a final...we've got to hit a good 8 or 9/10 for sure to win this game, I'm envisaging.
"We were pleased to beat Leicester the way we did. We thought there were a fair amount of areas we could improve on, and if you had been in the review for Toulouse you'd say the same thing.
"Even the Munster review, again, you'd think we had lost.
"So it's about setting the standards as high as you can, and making sure the players aim to achieve that.
"If you constantly have that as your mindset, then you should get more consistent at playing well in the biggest games.
"There's no guarantee - something can happen in the first minute and it changes the dynamic for the rest of the 80 minutes.
"So we're not really in control of the outcome, but all you can do is prepare them as well as you can.
"And I can say with confidence that we've done that this season and we're in good shape going into the final, and we're looking forward to it."
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