Four different injuries last season meant that he missed 22 out of 38 Premiership games as Ars-enal surrendered their title to Chelsea, and that he played in only three of England's 11 internationals. After returning for the final two League games, he had assured Arsène Wenger and everyone else that he was up for the Cup, only to find the manager choosing Kolo Touré and Philippe Senderos in Cardiff. If, as has been suggested, a cloud of depression hung over him, it was darkened by yet another injury, this time playing for England against the United States, eventually forcing his absence from the opening four matches of the new campaign.
Yet, back to fitness, back to form and back in the team, the Sol man-mountain looked bright enough at the end of last week, alternating throaty laughs and knowing smiles before his answers to a series of questions about a critical season for club and country. "Everybody knows how I was feeling," he said of the summer's frustrations. "Things are going to be said, blah blah blah. It happens, you can't get your way and play all the time like every footballer wants to. Sometimes you have just got to wait for your chance and then take it."
Take it he did, returning in triumph by heading two goals at Highbury against Everton. Since then, Arsenal have lost only in one other game he missed, at West Bromwich, while ensuring qualification for the knockout stage of the Champions' League with four straight wins.
And although two defeats in those first four Premiership matches - one of them at Stamford Bridge - had seen Chelsea galloping off into the distance, Campbell is not minded to give up the chase quite yet: "All you can do is look after your own team. You can't just give up. Things can happen. You can't win every single game, so you see how people respond [when they don't]. It's a long season.
"Our League form has been frustrating, there's been a lot of players in and out. Hopefully, now we're getting most of our players back we can settle down and get some performances and a run going. And in the Champions' League, we've been getting the breaks we haven't done in previous years."
The two games against Sparta Prague illustrated what a difference Thierry Henry and his goals make. Henry's captaincy is less impressive, and had Campbell been fit to start the season he would have been a more obvious choice as successor to Patrick Vieira.
As a 31-year-old, he accepts a degree of added responsibility for encouraging what is essentially a young side: "I think most of the players have taken it on themselves to lift their game, because Patrick going leaves big shoes to fill. The guys are coping and getting experience, and they'll kick on.
"You've got to compensate in certain situations, but the team spirit's fantastic and we've just got to keep it going. I've been vocal and we've got to demand more from each other as a team, realise chances like this don't come round too many times in a player's career: winning the championship, the European Cup or even World Cups."
For any player in the England squad, the World Cup looms large. As Campbell put it in the week Des Lynam began his new job: "It's countdown time now." Assured of a place in the 23 next summer as long as he stays fit, his task is to see off either John Terry or Rio Ferdinand to claim one of the two central-defensive positions.
Another belly laugh: "It'll be judged on how every player plays in the season and how they finish off and who's fit. I want to play, of course, and so does everybody else. It'll be up to the manager who he picks and who he feels can win games for him. I've had this situation all the time, when I was 21, 23, 25."
Campbell's summers are measured out in those odd numbers. At 21 he was a substitute during Euro 96; at 23 a bitter loser after having a goal disallowed against Argentina in the World Cup second round; at 25 ever-present for Kevin Keegan's unsuccessful European Championship side; two years later Ferdinand's partner in Japan and a goalscorer against Sweden; and then one of the few English successes at Euro 2004.
And at 31? A sunnier summer than this year's is the absolute minimum requirement.