Arsene Wenger is in the market for defensive reinforcements but is concerned that there are not as many natural leaders in the game as when he arrived at Arsenal.

The 65-year-old has struggled to name a consistent back four so far this season with the likes of Laurent Koscielny, Mathieu Debuchy and Kieran Gibbs all injured at some point.

Many of Wenger's critics believe the Frenchman made an error in not strengthening his defensive options in the summer – opting instead to spend the bulk of his transfer kitty on Chile forward Alexis Sanchez.

The former Barcelona man has been an instant hit at the Emirates Stadium but the Gunners sit sixth in the Premier League, largely down to their defensive deficiencies.

Wenger has acknowledged that a defender is required during the January transfer window but does not feel he can replicate the success of his great teams in the past.

Tony Adams, Steve Bould, Nigel Winterburn and Lee Dixon were his mainstays early on in his tenure and Wenger also highlighted the back four who featured in Arsenal's unbeaten season of 2003/04 as another outstanding unit.

But, with the game changing at a constant rate, Wenger believes there are a lack of aggressive-minded leaders to bring in.

"Certainly you had more before, yes," he said when asked if there were less leaders in the game today.

"If you look at the evolution of English football, when I arrived here I had the back four and all were English. But they were not only English, they communicated because they had the same culture, the same way to see the game, they were educated together and communication is an important part.

"We had a great defence after that, nobody spoke about them. The 'Invincibles' team were physically fantastic. Lauren, Kolo (Toure), Sol Campbell, Ashley Cole – that was a top back four.

"I believe as well that the young boys practice well on quality pitches, whereas before it was muddy and you could throw your body in – it created opportunities for defenders to work naturally on their defensive technique.

"Today it's all more about standing up (to opponents) and there is less physical commitment because the quality of the pitches is much better.

"Maybe, as well, because our societies are less aggressive, in the football education system you cultivate less that desire, it is more about the quality of the technique and maybe that creates less defenders."

Wenger admitted he had a "few names" on his list of defensive targets and pinpointed Chelsea's central defensive partnership of Gary Cahill and skipper John Terry as examples of the dying breed of defenders he is looking for.

"John Terry is a coach on the pitch," he said.

"He's a Tony Adams, basically, organizing the team because he has huge experience now and reads the game well.

"Maybe (Gary) Cahill in five, six, seven years will be like that as well. He is the right age and you do not find many any more. You had more before than you do today.

"With people coming in from different countries, communication has gone from the back four, much more than before and you see less people who talk.

"They do not always speak the same language, they do not respond to situations in the same way. That has gone a little bit from our game."

A more attacking philosophy, with a wealth of attacking options including Sanchez, fellow summer recruit Danny Welbeck, club-record signing Mesut Ozil as well as the likes of Theo Walcott, Alex Oxlade-Chamberlain, Santi Cazorla and Olivier Giroud, is also putting Wenger's defense more under the microscope.

"We are getting there," he added.

"It's not only that, I think we have more offensive players in midfield than we had at the time, it's not only the back four. I think the whole defensive unit, we are more offensively-orientated than we were at that time."

That defence is likely to be tested on Sunday as Stoke visit north London looking for their second win over Arsenal this season after the recent 3-2 victory at the Britannia Stadium last month.

Wenger is yet to decide whether goalkeeper Wojciech Szczesny will return following a reprimand for smoking during a post-match shower at Southampton, but Ozil and Aaron Ramsey could play some part after returning to training.