It has been dubbed the "battle of the capitals", but tomorrow will be more than a tale of two cities. While Brian O'Driscoll, Phil Vickery and Malcolm O'Kelly have played numerous Anglo-Irish games in their time, the countdown to the collision between Wasps and Leinster at Twickenham has been as intense as any.
Josh Lewsey said this week that the quality of the big Heineken Cup ties nowadays is frequently superior to Test rugby. If he is correct, and he has played long enough for club and country to have a well-developed sense of perspective, this game is as near as an uncapped player will come to experiencing a formal Test trial. When he looks across the halfway line, the Wasps centre Dominic Waldouck will see the great O'Driscoll, flanked by Felipe Contepomi and Shane Horgan, opponents who boast more than 200 caps between the three of them.
The 21-year-old Waldouck, once again named in the England Saxons squad this week, is among those who disagree that only gnarled old heads rise to the big occasion. No one is suggesting England should toss in 15 promising kids simultaneously, least of all Martin Johnson, whose rejigged elite squad contains 17 forwards, 10 of whom will be older than 30 by the end of 2009. But there is a difference between excessive caution and calculated risk, and days like this, according to Waldouck, are ideal for changing attitudes.
"Like all young players I'm very impatient and you want to be playing for England now, not in six months or a year," Waldouck says. "I think that's healthy. It just drives you on and makes you work harder at your game. You want to become the best you can be as quickly as possible."
You can sense the restlessness among those made to wait by thirtysomething stalwarts. Waldouck, the kind of quick-witted, alert centre with the priceless ability to make those around him look good, is a perfect example: of the competition in his specialist position, Mike Tindall is 30 and Jamie Noon soon will be. In some quarters there appears to be an innate suspicion of anything remotely fresh-faced; it is worth recalling that O'Driscoll first played for Ireland aged 20, while Jonny Wilkinson made his England debut at 18.
"I don't think age has got anything to do with it," says Waldouck, who has been a friend of team-mate Danny Cipriani since childhood, when the fly-half's father, Jay, taught Waldouck to swim. "If you're good enough you're old enough. I also don't think you can go into any game feeling you're inferior to your opposite man. Both of them [Tindall and Noon] have achieved a lot in their careers and you respect that, but when you play against them you want to do them over, come out ahead and prove a point. If everyone in your side does that, you'll almost certainly win."
Even the quietly confident Waldouck, though, cannot completely mask his excitement at the prospect of facing O'Driscoll, a player he idolised growing up. "To have the opportunity to play against him is a massive thing for me. I remember watching the Lions tour of Australia in 2001 and some of the stuff he did out there was just outstanding. He was a pretty young guy at the time as well [he was 22]. You just have to prepare for these kind of occasions as best you can. You don't want to get too psyched up because otherwise your game will suffer."
A talented all-round sportsman, Waldouck was a member of Fulham football club's academy and also played cricket for South-East England Under-16s. He scored a try on his debut for England Under-16s and does not appear to be a young man in obvious danger of being overawed.
Wasps, for their part, simply cannot afford to finish second best. Having gone down 41–11 in the reverse fixture in Dublin, there will be no way back in Europe this season if they fold meekly again before an audience of more than 30,000. Given they have nine players in England's elite squad and a further liberal sprinkling of Saxons, the full attention of Johnson and Brian Smith at Twickenham is also guaranteed.
Sending the Celts home to think again would clearly be a bonus with the Six Nations approaching, if not a copper-bottomed guarantee of the national side carrying all before them in the next two months. It is certainly a timely opportunity for Cipriani, needing to evade such players as the canny former Wallabies Chris Whitaker and Rocky Elsom, to restate his top-level credentials. Waldouck will be right there in his fly-half's slipstream, fully aware the big Heineken games make no allowances for youth.
"There's so much riding on it that everyone wants to play quicker and hit harder. Five minutes in you're gasping for breath and it can be a shock to the system. I guess that's what Test-match rugby would be like, but it's addictive. You want to be in more of these games and experience the joy of winning them as well."
The probability must be that Waldouck will indeed satisfy his craving for an England cap in the not-too-distant future, perhaps this summer in Argentina. In that event, the only thing that would make the moment sweeter would be Cipriani's presence alongside him.
"To play with Danny in a white shirt is a dream," Waldouck says. "Hopefully we can do it sooner rather than later. I had a good chat with Brian Smith at the start of the season; he was very encouraging and, from a back's perspective, what he's bringing to English rugby is very good. Creativity, good organisation ... I'd like to think I could contribute in those respects. It's just a matter of showing everyone on the pitch on big occasions like this."