For more than two years, Wenger's collisions with Birmingham City have been spiked by memories of the badly broken leg that Eduardo, the former Arsenal striker, sustained in Feb 2008 under a horribly mistimed challenge from Martin Taylor. By common consent, the Brazilian-born forward has never rediscovered his best form since, and the same fate could easily have befallen Nikola Zigic after his ankle was scythed by Wilshere's studs.
Arsenal v Portsmouth previewWith the richest irony, Wenger had used his programme notes here to form another tirade against the worst of Premier League tackling, arguing: 'Everybody needs to fight against violence.' Even in the aftermath of Wilshere's dreadful lapse, the Arsenal manager stuck fast to his view that his players were more sinned against than any in the top flight but said of his 18-year-old midfielder: 'He got a red card and he deserved it. But he was one of the best players on the pitch - you cannot say he had a dirty game.'
Wenger became more tetchy when pressed on Arsenal's unusually physical approach. Emmanuel Eboué had also risked being dismissed in the second half for an ugly 'scissor' challenge on Liam Ridgewell. Refusing to extend the criticism to his right-back, he said, blankly: 'Let's go to the next question.'
Wilshere's unseemly rush of blood could not be passed off as an aberration for Arsenal, for whom it brought a third red card this season. The sadness for the teenager was that the moment disfigured his pivotal contribution to this match, one he influenced no more artistically than in the neat interplay that produced Marouane Chamakh's winner.
His afternoon ended, however, in madness. His studs could have been seen from every side of the Emirates as he tore into Zigic, taking out the Croatian's standing leg. The time and place - the third minute of injury time in a game where Arsenal had all but wrapped up victory, and deep in Birmingham's half - were painfully misjudged. Wenger confirmed that he had spoken to Wilshere, who automatically received a three-match ban, but he would have been equally well-advised placating his opposite number, Alex McLeish.
The Scot was seething over Arsenal's apparent hypocrisy. He described the representation of Taylor as a dirty player as 'scandalous'. McLeish said: 'We all know Wilshere is not dirty, but this shows you that bad tackles do happen in this hurly-burly game of football. Eduardo suffered appalling damage but Zigic could have been damaged, too.'
Both teams could be relieved that Zigic hobbled out of north London nursing nothing more serious than a sore ankle. But Arsenal's satisfaction was the greater after they rallied from the setback of this beanpole striker's first-half strike to stop a three-game winless streak.
Momentum ultimately shifted in Arsenal's favour. First Samir Nasri, dispatching a penalty after Chamakh had gone down under limited contact from Scott Dann, settled the nerves and then Chamakh himself combined with Wilshere for an assured finish.
'Our fluency was a bit affected,' Wenger said. 'We played with a bit of a handbrake in the final third. We had our backs to the wall, considering the championship. We had absolutely to win.'