Lewis knows only too well that he should have fought Evander Holyfield, Riddick Bowe, Mike Tyson - even George Foreman. He also knows that it's too late now for these contests to have the impact they would have had a few years ago.
Holyfield's epic regeneration of his career against Tyson is receding into the past. The man who calls himself "The Real Deal" is now 36. He has no apparent interest in proving himself any more. Bowe, the youngest of the quartet, is done with boxing. Two hollow victories over the erratic Pole Andrew Golota, when he took a hammering before winning on disqualification, finished him. Bowe has flopped as a trainee US marine, parted from his wife and family and has also reportedly shown frightening signs of having been damaged by his ring career.
Tyson's slide into the social mire has been well documented and his two defeats by Holyfield have exposed his fading power. At 32, Tyson is a year younger than Lewis, but his brutal life has aged him far more that the big Englishman, who could still pass for a man of five years younger. Because of his speed and punching power, Tyson will probably remain dangerous in world class for some time, but the next man to beat him will not gain the same benefit from victory as did Holyfield and his first conqueror, way back in 1990, James "Buster" Douglas.
And Foreman, who celebrates his 50th birthday in January by fighting another relic, Larry Holmes, is so old that to match him with Lewis would now be cruel. As tough as old George remains, even boxing's unsentimental movers and shakers would acknowledge that to put the old fellow in with Lewis would be akin to encouraging one's grandfather to get himself beaten up. Nobody, least of all Lewis, wants that.
And so, what is left for Lewis is a series of fights against unproven challengers, whose reputations will not enhance his own until the time he gives us a better perspective. Although Mavrovic has won all 27 of his professional fights, reads Tolstoy and has an astrologer for a girlfriend, nobody really knows how good he is or might become. Win or lose against Lewis, it may not be this fight which carves out what the 6ft 3in Croatian will mean. He must prove himself over time and in more world-class contests.
To the WBC champion, Mavrovic is on the same level as his recent opponents Oliver McCall, Henry Akinwande, Golota and Shannon Briggs. He brings a degree of talent and therefore represents a threat, yet has not established himself as a man of the highest class. Should he beat Mavrovic, Lewis will face more of the same. The queue is forming. On the undercard next week, on the Native American reservation at Uncasville, two would-be challengers slug it out. Either of them, Hasim "The Rock" Rahman of Baltimore, or David "The Terminator" Tua, a Samoan who lives in the States, could fight Lewis next. An alternative is Lou Savarese, an Italian-American whose reputation rests on a close points defeat by Foreman and a one-round win over a 38-year-old Douglas earlier this year.
There were years of being slaughtered by the American press - long-lasting jibes of "Garbage Can Champ" after he inherited the belt which was famously tossed into a bin by Bowe in a publicity exercise. Now Lewis has earned grudging respect in the States. Some still harp back to his solitary defeat, by McCall in 1994, as proof of a glass chin. Most accept him as a man who has a case for arguing that he is the best heavyweight of his time.
In itself, a win over Mavrovic will not provide weighty evidence for the cause, but it is acknowledged that his victories are now accumulating. He avenged the defeat by McCall by stopping the emotionally traumatised American in five strange rounds in Las Vegas in February 1997. The sight of McCall being led away by the referee Mills Lane was harrowing. He wept as if grief-stricken. After that, Akinwande was disqualified for incessant holding. Again it was Lane who ended the farce by guiding the 6ft 7in, London-born Nigerian roughly to his corner. Akinwande, whom some felt had the technique to beat Lewis, folded mentally.
Golota's demise, in Atlantic City in October 1997, was psychological as well as physical. The Pole, who had given Bowe nightmares twice, froze and was knocked out in a minute and a half. Afterwards he was taken to hospital, not because of any physical damage, but because he suffered a panic attack.
Lewis's last opponent, Briggs, did far better because he was not intimidated. The 25-year-old New Yorker shook the champion in the first round of a thrilling encounter which lasted five. But the end result was similar: Briggs was down three times and had to pay grudging tribute to a man whom his national press pilloried for so long.
Now it is the turn of Mavrovic, who is unlikely to be psyched out and whose main assets are speed, confidence and a good game plan. Almost certainly, he will not try to beat Lewis early on, but will look to defend for four rounds and then attempt to test the stamina of a man who has not needed to go beyond five rounds for more than two years.
It might work, but probably won't. Lewis has come too far now to lose a fight like this, but may have to go six or seven rounds before he can provide another piece of evidence for his long-term case.