After defeat to Tottenham on Sunday, the capture of Pierre-Emerick Aubameyang is looking more and more like a palliative for Arsenal.There is no doubting that the Gabon international will bring goals to the Emirates Stadium and, alongside Henrikh Mkhitaryan, Arsene Wenger has done well to address Alexis Sanchez's exit but, crucially, their defensive problems remain.It seems every pundit who has discussed Arsenal in the last month has cited the club's lack of defensive reinforcements with Wenger failing to capture Jonny Evans on Deadline Day.The man himself even conceded: "Our defensive numbers aren’t good enough. We needed strengthening because we have to improve our defensive numbers to make the top four."You don't say, Arsene. 

Arsenal didn't invest in a defender over January

Arsenal reportedly baulked at the asking price for Evans despite shelling out heavy transfer fees for Aubameyang and Alexandre Lacazette in recent months. Furthermore, supporters and pundits alike have even questioned why Arsenal didn't move for Virgil van Dijk.

It seems the Dutchman always had his heart set on Anfield, yet you'd like to think Arsenal would throw their hat in the ring if they were as worried about their defence as they claim. 

Jamie Carragher and Thierry henry had this very debate on Monday Night Football and the latter, having worked under Wenger for eight years, had an interesting theory on Wenger's behaviour.

The Sky Sports expert believed that Wenger isn't a fan of the inflated expenditure on defenders that has been particularly apparent at Manchester City recently. 

Thierry Henry's theory on Arsenal leaving Van Dijk

When Carragher asked why Wenger didn't pursue Van Dijk, Henry mused: "Maybe he doesn't see it as a problem, when we all can see it is.

"Why didn't he go for Van Dijk? I think, in the history of Arsenal: Kolo Toure was almost nothing and Sol Campbell was nothing.

"But now, clubs will ask a price that goes beyond what it should be.

"This is the story with Arsene, it seems like people always say that he doesn't want to spend big and he always thinks that some of the players aren't worth the price on the table.

"But it's a new era. If you want someone good you need - £60 million, £70 million whatever the position is and I think he finds that very difficult."

Henry could be onto something here and Arsenal fans won't like to admit it.

Perhaps a downside of Wenger's reign transcending eras is his inability to move with the times. 

The Aubameyang signing suggests the Frenchman isn't truly immune to spending big, but he might have to accept that crazy transfer fees aren't reserved for strikers anymore.

Do you think Arsenal should have moved for Van Dijk? Have your say in the comments section below.