We like to think we’ve watched enough football that we won’t be surprised by much these days.
A goal from the halfway line? Seen it before. A player running the length of the pitch? Who hasn’t done that? An inch-perfect free-kick? Zzzzzz.
However, back in 2004, Kanu managed to produce something we have never seen before or since: a miss so bad it almost defies explanation.
The season was just a dozen games old, and Bryan Robson – newly installed as manager after Gary Megson’s sacking – was in charge of his first game as West Brom boss.
Albion were in the bottom three with nine points from their first 12 games, but victory in their Sunday game at home to Middlesbrough would lift them back out of the drop zone.
Boro went ahead through a Darren Purse own goal and restored their lead through Bolo Zenden after Rob Earnshaw had brought the home side level.
As the clock wound down, though, Cosmin Contra burst into the box and fed substitute Geoff Horsfield, who fired in a low ball across the face of goal for Kanu to tap in from less than a yard out… except he didn’t.
This is how a player with countless trophies, a host of big-game performances and a career to die for has, for some, been forever associated with his lowest on-pitch ebb.
We’re no scientists here, but we studied a bit of physics at school and we’re pretty sure there’s no way what Kanu did is supposed to be possible.
Based on the direction of his leg, the direction of the ball and the placement of the goal (and we’re fairly confident the last of these is fixed), any contact ought to have sent the ball into the net.
At a stretch, we could see him missing by opening up his body and seeing the ball skim off him, or by swinging and missing, but this man is a professional footballer; a striker, no less. It’s literally his job not to do these things.
The miss itself isn’t what makes this such an iconic moment, though. No, that accolade is saved for the reactions. Horsfield spins away, literally reacting faster and with more focus than when Contra played him in.
Contra himself turns towards the same touchline, albeit after a little jump on the spot as he tries to figure out exactly what has just happened.
Are they both turning as far away from Kanu as possible because they’re scared to look him straight in the eye? Almost certainly.
At least Kanu himself has a natural reaction, sitting – decidedly sitting, and not kneeling – while staring at whomever or whatever has wronged him.
He will remain there until he has identified the culprit, which fortunately happens when he catches his own reflection in the goalpost.
Were it not for that slice of good fortune, he might still be on the ground at the Hawthorns today, which would be a nightmare for anyone trying to enforce the offside rule.
Finally, though, we turn to Robson.
The manager was treating this game as a chance to see what his newly-inherited squad was like when push came to shove. Not very good, it turns out.
Even so, he can’t have expected what happened after Horsfield put in a cross which an inanimate carbon rod would have been able to turn into the back of the next.
While other misses might leave managers turning away in disgust, there was no place for that here.
Disgust requires some understanding of what took place, and there was none of that here.
Robson’s reaction is more like a double-take, trying to determine whether what he witnessed was even possible or whether he had suddenly begun hallucinating. His former Manchester United team-mate had famously missed an open goal nearly a decade earlier, but this was on another level.
“It seemed far easier to put it in the net than over. It looked impossible,” Robson said after the game. Even now, that feels like an understatement.