Arsenal enjoy the last laugh despite Southampton defender Virgil van Dijk's dirty tricks

Bobby Madley brandished so many yellow cards and warnings after awarding a deeply controversial late penalty that the bizarre, real reason for Virgil van Dijk’s booking became almost lost in a haze of Southampton anger. It later emerged, however, that Van Dijk became one of the very few players in football history to be cautioned for an attempt to damage the penalty spot before Santi Cazorla’s 94th-minute winner.

It is understood that some Arsenal players suspected similar foul play when Cazorla slipped and missed a late penalty against West Bromwich Albion last season. 

Although Cazorla was unaffected this time, Van Dijk did later admit to an act of gamesmanship. “Well, yeah, it’s a penalty in the last minute so you try to do anything to prevent the goal and that’s what I did but it didn’t work,” he said.

Southampton’s sense of injustice came with Jose Fonte, who had been jostling with Olivier Giroud, claiming that the Arsenal striker had subsequently asked him who gave the penalty away. It was certainly the sort of innocuous and diluted incident that does not usually result in a penalty, especially amid the additional complication of Laurent Koscielny still lying dazed in the penalty area after being inadvertently kicked in the head by Fonte. Southampton goalkeeper Fraser Forster was signalling for medical assistance and the rest of his team did also seem to hesitate briefly immediately before Arsenal won their penalty. “It was pretty strange and there were players on our side who were also looking a bit confused,” said Van Dijk. 

Arsène Wenger admitted that Arsenal were fortuitous in those final minutes of the match but also revealed that Koscielny’s eye had closed and that his captain was now a doubt for Tuesday's first Champions League fixture of the season against Paris St Germain.

The absence of Koscielny would mean starting Rob Holding at centre-back in what would be a first Champions League match barely a year since he made his Championship debut for Bolton Wanderers. 

Wenger will make a final decision on Koscielny this morning but it was certainly an eventful 31st birthday for the Arsenal captain. As well as his eye injury, Koscielny equalised with a spectacular overhead kick after Dusan Tadic’s free-kick had gone back into the Arsenal goal off Petr Cech. Despite being a quiet off-field presence, Koscielny certainly seems to have grown in stature since becoming captain. 

“He is one of the most experienced players we have now here,” said Wenger. “When you choose a captain, you think of one with a good chance to play in every single game and that’s not easy. He has committed to the club for a long contract and he has always improved every year. He doesn’t score when it is 4-0, he scores at 1-0 down. He will be a concern for PSG.” 

Other changes are certain elsewhere within an Arsenal squad that Wenger expects to rotate more than ever before. Granit Xhaka, Alexis Sánchez and Oliver Giroud were all substitutes on Saturday and will surely start at the Parc des Princes. Asked if it was now his strongest ever squad, Wenger said: “The strongest and certainly the oldest as well. With the quantity of games you cannot always play with the same players.” He also urged patience on judging new striker Lucas Perez, who was largely anonymous for the 62 minutes he did play.