The secret to Michael Cheika's success with the Australian rugby side lies in his ability to scare the wits out of his Wallabies, according to Ireland first five-eighth Johnny Sexton.
Sexton was coached by Cheika at Leinster when the Irish club won their first-ever Heineken Cup title in 2008.
However Sexton said Cheika backs that up with deep-thinking insight and shrewd coaching acumen.
England bombed out of their home World Cup just 16 days into the tournament, beaten 33-13 at Twickenham by Cheika's rampant Wallabies at the weekend.
Lancaster is now fighting for his future, while former Leinster and Waratahs boss Cheika is riding high, less than a year into his first Test-level assignment.
When asked why Cheika is such a proficient coach, Leinster pivot Sexton replied: "Because everyone's probably scared s***less of him, if I was being honest!
"He knows his rugby as well, he's a very clever guy but he does have that presence where he's a pretty scary guy when you get on the wrong side of him."
Sexton and Cheika have kept in contact since their time at Leinster just as the affable but focused Cheika seems to have managed with the majority of players he has ever coached.
Sexton hailed Australia as one of the new World Cup favourites after their fine early-campaign form, while also admitting he will aim to meet up with Cheika once the tournament comes to a close.