Martin Johnson admits he may struggle to come to terms with retirement when he bows out of rugby on Saturday.
Twickenham, 4 June
Kick-off 1930 BST
Johnson's select XV take on a Jonah Lomu-led side in the former England captain's testimonial at Twickenham.
"It's not really sunk in that Saturday is it," Johnson said. "Maybe it will in September when the new season starts.
"I've come to the end of my time and I need to move onto other things now. But I can walk off the pitch very proud of what I've achieved in my career."
Johnson includes a number of former club and country team-mates in his side, including fellow World Cup winners Joe Worsley and Kyran Bracken.
There would have been a third, but Simon Shaw's Lions call-up means he is replaced in the second row by Sale's Chris Jones.
The match will also be significant for Lomu's return to competitive rugby after three years away from the game with major kidney problems.
"I'm 35 and I've been very fortunate with injuries throughout my career," Johnson added.
"When I hear what Jonah has been through that just makes me realise how lucky I've been.
"I'm delighted he is playing this weekend. He is certainly one of the biggest names in the game and hopefully this will be a successful first step back for him."
Lomu, who will have a dozen All Blacks in his 22 and two ex-Wallabies in Matt Burke and Toutai Kefu, is delighted to be part of Johnson's farewell proceedings.
"It's just a privilege to run out on the paddock with him for his last game," Lomu said.
"He's done a lot for world rugby. He's unique in terms of his talent and leadership and for the team and myself it's an honour to run out on the pitch with him."
Martin Johnson XV: Gregor Townsend; Austin Healey, Tony Marsh, Jamie Noon, Ayoola Erinle, Andy Goode, Kyran Bracken; Tom Smith, Raphael Ibanez, Darren Morris, Martin Johnson (capt), Chris Jones, Joe Worsley, Olivier Magne, Sebastien Chabal.
Replacements: Jonathan Humphreys, Will Green, Victor Costello, Anthony Foley, Will Johnson, Morgan Williams, Rob Henderson, Leon Lloyd.
Jonah Lomu XV: Bruce Reihana; Lome Faatau, Matt Burke, Daryl Gibson, Jonah Lomu (capt), Carlos Spencer, Mark Robinson; Kees Meews, Daniel Coetzee, Dave Hewitt, Greg Rawlinson, Troy Flavell, Justin Collins, Corne Krige, Toutai Kefu.
Replacements: Trevor Leota, Craig Dowd, Ian Jones, Scott Robertson, Jason Spice, David Howell, Keith Lowen, Eric Rush.