England's three-cap centre Luther Burrell has to find a way to control the 139-test Ireland legend Brian O'Driscoll - and he cannot wait to have a go.
Burrell is well aware of the danger posed by O'Driscoll, all too acquainted with that feeling of embarrassment when a player of rare quality conjures something magical and leaves his opponent grasping at thin air.
Burrell was the fall guy in a Heineken Cup tie in December when he was closing in to make a king hit on the veteran Leinster centre as he took a pass under pressure. He was left empty-handed as O'Driscoll bent and flicked the ball through his legs to Rob Kearney, who sent Luke Fitzgerald in for a try in the corner.
No wonder Andy Farrell, the England backs coach, has hammered home the need "to expect the unexpected". No wonder Burrell professes that this will be "my toughest defensive challenge yet". And no wonder he expressed his bafflement as to why anyone should have considered dropping O'Driscoll for the third Lions test in Australia.
"I didn't think for one second that it was deserved," Burrell said as England went through their routines at Twickenham ahead of Saturday's RBS Six Nations game against Ireland.
The feeling of shock and awe at O'Driscoll's outrageous skill in that Heineken Cup match was not confined to Burrell. Northampton were humiliated by Leinster, who won 40-7 at Franklin's Gardens, O'Driscoll's party trick just one of several highlights.
That experience, and the way Burrell and his colleagues rose from the canvas to strike back seven days later with victory in Dublin has served as both a warning and a boost. If O'Driscoll and others are allowed free rein, they will expose any shortcoming mercilessly. But, equally, as Burrell found out, if their intensity is matched with fervour as well as intelligence, Irish sides are far from unbeatable.
Burrell is playing only his third test while O'Driscoll will equal the world record of 139 caps. One is callow, raw and unproven, the other a master.
Burrell cannot deny the gulf. However he has no intention of letting his evident admiration for O'Driscoll extend beyond kick-off. Icons are there to be dismantled as much as they to be worshipped.
"It was me closing in on Brian when he did that pass straight between his legs," Burrell said with a rueful smile. He didn't even look where the ball was going and it went straight to hand. He is just one of those players who has got that X factor. Brian is a fantastic player with a lot of flair in his attacking game. He is good over the ball, has good offloading and can kick well.
"But I feel as ready for this as I am ever going to be. I am under no illusions that this game is going to be a step up. I am going to respect Brian, honour the occasion and pick his brains afterwards, but for 80 minutes we will be enemies."
O'Driscoll has been this way many times. For Burrell it is a first, a Twickenham crowd expecting their man to put a great big dent in a legend. Scott Williams, the Wales centre, tried and failed in Dublin two weeks ago, O'Driscoll rising from the turf after one thunderbolt tackle.
There is far more to the mosaic of defensive play, though, than headstrong tackling. It is about cleverness and timing as much as emotional commitment. The striking thing about Burrell's entry into the international arena has been his composure. He has scored two tries in two matches, played with fervour as well as verve, all in the unfamiliar position of outside, rather than inside, centre.
Burrell's big-game temperament has certainly made its mark on the England coaches. "Luther has always looked from day one as if he fits," Farrell said. "He has been great. His self-confidence is the most impressive thing. Brian can turn a game on its head but I am sure that Luther will back himself."
Of course he will; Burrell would not be anywhere near an international squad if he did not. There is a reassuring stillness and self-effacement about Burrell, underscored by an assurance in his own ability. He has not looked a novice, in defence or attack. In fact, he has looked the more settled of the centres, with Billy Twelvetrees still prone to the occasional glitch.
England will need to hunt together.
Much as O'Driscoll is capable of sprinkling gold dust by himself on a match, his alliance in the centre with Gordon D'Arcy has the capacity to make merry with any opposition, all the more so with Johnny Sexton inside them at first five-eighth. O'Driscoll and D'Arcy racked up a record 53rd appearance together against Wales.
"Above all, you have to be smart defenders against these guys, really on the ball," Farrell said.
Ireland's kicking game against Wales was probing as well as varied; they pinned Wales back on the flanks and took advantage.
Joe Schmidt, the Ireland coach, is sure to have a different strategy worked out for England.
Burrell is under no illusions as to what lies ahead of him.
"You know you are going to have to be at your best or you will be found out," he said. "Ireland attack that wide channel so we know we have to be on our mettle."
And with an eagle eye trained on O'Driscoll, the trickster par excellence.
• England v Ireland: Twickenham, 4:50am tomorrow