From the moment Harry Maguire was introduced at half-time of England's win over Scotland last night, he was relentlessly targeted by the Tartan Army.
Sensing a potential vulnerability in an otherwise imperious England, the home fans roared in mock anticipation whenever Maguire was on the ball, ironically jeered every simple pass he completed and even chanted his name.
By the end of a tempestuous night, it was the pocket of England fans in Hampden's south-west corner who were singing for Maguire, as Gareth Southgate's side came away with a 3-1 victory over their oldest and fiercest rivals, but the defender's introduction changed the feel of the whole occasion.
Far from confirming England's dominance, Maguire, who replaced Marc Guehi, only lifted the home crowd and, by extension, the Scotland players.
And the Tartan Army's pressure paid off when Maguire turned Andy Robertson's cross into his own net in an unfortunate but sloppy piece of defending, halving the deficit and giving the hosts a way back into the friendly.
When the stadium announcer confirmed it was a Maguire own-goal, it prompted the biggest cheer of a deafening night.
Maguire's status with England has been the subject of almost relentless discussion for well over a year now, and in some respects there is little left to say: he is short of confidence and form but still in credit with Southgate, who puts huge value on his performances at the last three major tournaments and believes that the 30-year-old remains an important player for England, despite two dreadful seasons for Manchester United.
Last night, however, felt like a tipping point in that it was easy to wonder if Southgate's loyalty is becoming detrimental to Maguire himself, as well as the rest of the team.
Southgate afterwards offered a passionate defence of Maguire, saying English "commentators and pundits" had "created something that is beyond anything I have ever seen", but the manager is feeding the narrative by keeping faith in a player who plainly does not deserve to be in the squad on current form.
Southgate may believe his loyalty is boosting the beleaguered defender, but putting him in the firing line in Glasgow felt misguided at least, not only because it served little purpose in footballing terms.
Would it not have been better to blood 20-year-old Levi Colwill for 45 minutes and see how he coped with the occasion?
It was genuinely uncomfortable to witness a player low on confidence being targeted by supporters, even if Maguire has shown he is mentally strong enough to cope with all manner of abuse.
The bottom line is that Maguire has never felt more like an Achilles heel for England — and the Scots knew it and ultimately exploited it.
England will play in few atmospheres as ferocious and against such a close rival, but the same will be true of other opponents in more important matches if Maguire's continues to struggle at United.
It is surely time for the manager to start picking his England squad, not to mention his teams, on merit, rather than past performances and reputation.
