Last year, Brown took the field by surprise in Brussels when he strolled to an astonishing 35-second victory over Paulo Guerra, the Portuguese runner who won the first two European titles, in Alnwick, Northumberland.
Radcliffe, who established her credentials as a teenager when she won the world junior championship in the snow and sub-zero temperatures of Boston in 1992, came of international age when she took the silver medal in the senior race last March.
Neither is in Lisbon this year for what promises to be a wide open meeting. Brown is recovering from a hip injury while Radcliffe is honouring a long- standing commitment to run the Honolulu Mile.
But Clarke insists that memories of what they did to lift the image of British running will ensure their colleagues give everything they possess to achieve medal-winning performances.
"The spirit of what Jon achieved in Belgium 12 months ago still lingers," said Clarke, whose own competitive experience in major championships over 17 years has helped bring him considerable success since his appointment two years ago.
"Flying over, the team members were still talking in awe of how we thrashed Europe's best. Now they want to do the same, and I would say if Keith Cullen hits the form he is capable of he will come away with a medal of some description. Likewise Andy Pearson, who won a bronze medal two years ago, is in the same frame of mind to be a dangerous threat.
"Both of them have strong backing in the shape of Christian Stephenson, Chris Robinson, Dermot Donnelly and Dominic Bannister to make serious challenges for the team honours.
Clarke said he would not make the mistake of underestimating the opposition. "Spain have a very strong squad led by the world marathon champion, Martin Fiz, while Portugal, although weakened, will want to perform well on their own patch. But the boys really have the bit between their teeth and are eager to come up trumps."
Clarke also believes the British women can at least equal the team silver medal they won in the mud of Belgium, albeit with a brand new line-up this time.
"There's a buzz about them - particularly Liz Talbot, Radcliffe's team- mate at Bedford," Clarke said. "They've come here totally committed, and I think Liz, supported by Vikki McPherson, who is in the form of her life, are capable of being more successful than they both realise."
After yesterday's Heathrow Airport fire the team were transferred to flights from Gatwick, and all team members arrived more or less on schedule.
"The help from British Airways staff was fantastic," Clarke said. "Indeed, I think it will have acted as yet another motivating factor, knowing people really care about British sporting teams."