Dave Kilcoyne hopes Ireland can use their record loss to England as a World Cup cautionary tale.
Ireland climbed to the top of the world rankings for the first time with Saturday's 19-10 victory over Wales to toast boss Joe Schmidt's final match in Dublin.
Head coach Schmidt's men have hit back from their 57-15 humbling at Twickenham in August by beating Wales home and away, leaving Munster prop Kilcoyne boosted by that return to form.
And now the 30-year-old front-rower has insisted Ireland must keep on using that hefty London loss to fuel their drive at the World Cup, with their Pool A opener against Scotland fast approaching on September 22.
"I thought we were poor against England, there's no point denying it, I thought we lacked hunger and physicality which was the most disappointing thing," said Kilcoyne.
"We've an incredible defence coach in Andy Farrell, we all knew our defence was off that day, but thankfully that's really picked up in the last two weeks.
"And hopefully we can bring that into the World Cup, and really bring that impressive defence into the World Cup.
"You have to be equipped to turn negatives into positives. You can't dwell on it.
"If you keep looking back you'll never go forward and you get lost back there.
"So after the England game it was about looking at where and why we were short, and putting a plan in place to remedy that.
"I thought we did that well, and it feels we're building nicely now."
Rob Kearney, Tadhg Furlong and James Ryan all crossed as Ireland subdued Wales for the second time in as many weeks at the Aviva Stadium on Saturday.
Schmidt has carried Ireland from eighth to first in the world rankings in his six years at the helm, transforming the national team into a genuine world threat.
Former schoolteacher Schmidt will return to his native New Zealand after the World Cup, stepping down from his Ireland role to spend more time with his family.
The 53-year-old will leave with every Irish plaudit already in the bag, and Leinster wing Jordan Larmour believes that all boils down to his fiercely intense attention to detail.
Larmour was still a schoolboy the first time he met Schmidt, the Ireland boss turning up unannounced to watch the pacy wing feature in a Blackrock College President's XV clash against touring Kiwi side Hamilton Boys High School.
St Andrew's College student Larmour guested for Blackrock that day, and had the honour of meeting Schmidt too.
Fast forward less than two years and Larmour was being invited to train with Ireland's senior side having already stood out for the country's Under-20s.
When Schmidt wants a player to emerge quickly, he leaves no stone unturned in helping accelerate that process.
"The first contact I had with him was when I was playing in that club match," said the 22-year-old Larmour, of Schmidt.
"Then I went into the Ireland camp when I was in the Under-20s.
"It's hard to put into words what he's given to Irish rugby. His attention to detail, his man management, it's incredible.
"He's one of the best coaches I've ever had. So we're pleased with how we went against Wales.
"Going into camp, the attention to detail he has, going through the video and things, he's been amazing.
"We wanted to put in a performance for Joe (Schmidt) and Rory Best, they've given so much for Irish rugby. So we're pleased with how it went.
"We're certainly pleased with the performance but we've still got a lot to work on.
"We've got to keep on building. I wouldn't say it's our best performance of 2019, but it's a step in the right direction."