The teenaged team-mates, now in their forties, are sure to have aged further by the time the final whistles sound at The Dell and The Valley. For one of the pair, it will suddenly be Super Sunday. For the other, Black Sabbath.
Southampton go into their match against Jones' boyhood heroes and first club, Everton, in the stronger position. With more points, they know that any victory, however untidy, will guarantee a 22nd successive season in the top section, even in the unlikely event of Charlton running up a record win against Sheffield Wednesday.
The Saints could actually lose and stay up, provided Charlton are also beaten. But a stalemate on the South Coast and a home win in south London would see Curbishley's men avoid an instant return to the Nationwide League by virtue of a superior goal difference.
Straightforward as it may sound, experience shows the potential for twists and turns is boundless. The reaction of Southampton's players and fans to last weekend's win at Wimbledon suggested they felt they were all but secure, so complacency, or at least the feeling that they have one foot in the comfort zone, may be their biggest enemy.
Charlton must also be heartened by an Everton revival inspired by Kevin Campbell, who could be playing his last game for the club unless Walter Smith is given the pounds 3m needed to sign him. The Merseysiders certainly appear more dangerous than Wednesday, who have been more like pussycats than Owls since a Uefa Cup place via the Fair Play League loomed into view.
On the other hand, Southampton's unbeaten home record stretches back nine games whereas Charlton have won just four times at the ground they fought so hard to reclaim, and indeed have mustered only three of the last 15 points available there.
At the end of the day, which will come around 5.45pm, the club promoted after a penalty shoot-out last May could well be left ruing two recent misses from the spot that would have turned draws into wins.
Neither side is likely to suffer a Blackburn-style shortfall in resilience. Battling against the drop is a way of life for Southampton - even that managerial Jonah, Alan Ball, kept them up in eerily similar circumstances five years ago - while Charlton's response when they stared relegation in the face at Aston Villa last Saturday spoke volumes for their spirit.
Intriguingly, Southampton's result may dictate whether they can afford to build a pounds 30m, 32,000-capacity stadium. Such matters, however, must be the last thing on the minds of the combatants, according to one manager involved tomorrow.
Drawing on his unhappy experience with Barnsley 12 months ago, Wednesday's Danny Wilson vividly articulated the tension Jones and Curbishley will endure. "It's torture on the sidelines, far more so than when you're playing," he said. "Lots of things go through your mind, like `can I change things by bringing someone on?' and all the time people are shouting out the other scores. You go through every emotion.
"The main thing is to try to focus everything on yourself. You can't let your mind wander to the other matches. You know the crowd will have their radios on, and a roar will go up if another game goes one way or a groan if it swings the other. You've just got to keep going."