Arsenal have been urged to splash out on a defensive midfielder during the ongoing January transfer window by Liverpool legend Dietmar Hamann.

The former Bayern Munich midfielder feels that the Gunners have an exciting squad when it comes to attack, but believes they lack a midfielder, who can sit in front of the back four and break up play when the team loses the ball up the field.

Arsene Wenger has been on the market for defensive signings, but has failed to sign any experienced players thus far in the transfer window. The club's sole acquisition has been 17-year-old defensive midfielder Krystian Bielik from Legia Warsaw.

"Arsenal are a fantastic team, with some of the most exciting attacking players in the Premier League. But, for me, their strength is also their weakness," Hamann said, as quoted by the Mirror.

"Sanchez, Welbeck, Giroud, Santi Cazorla, Wilshere, Ozil and Oxlade-Chamberlain are as good as you will get, going forward. At the other end, Koscielny, Mertesacker, Gibbs and Debuchy are all reliable defenders."

"But what Wenger hasn't got – and hasn't had for years – is a defensive midfielder of the calibre of Nemanja Matic and John Obi Mikel at Chelsea; or Fernando and Fernandinho at City," the former Liverpool favourite explained.

"It is the most important area of the modern game. Having a player with the discipline not to get caught out of position, the intelligence to recognise danger and the ability to snuff it out before it becomes a problem for his defenders."

"Patrick Vieira was the master. He was the best in the business for years and one of the main reasons why Arsenal were so successful."

Hamann is at a loss for words as to the reason behind Wenger not addressing such a glaring problem, and believes that a lack of a defensive midfielder is the sole reason for Arsenal lagging behind Premier League title favourites Manchester City and Chelsea.

"So, I can't ­understand why Arsene Wenger hasn't addressed the problem. It's been holding his team back for too long now and it's the reason why the title is between City and Chelsea, with Arsenal fighting for fourth place yet again."

"There are players out there, who would instantly make Arsenal a better team. They are supposed to be looking at Ilkay Gundogan at Borussia Dortmund. He's a very good footballer – but he's a typical Arsenal player."

"He won't want to do the dirty work. His instinct is to join in further up the pitch, get a few forward passes going and try to weigh in with a few goals," Hamann said.

The former Bayern Munich midfielder has urged Wenger to spend big and land a top quality holding midfielder, and he has suggested the names of Germany's Lars Bender and Sven Bender, who play in the Bundesliga with Bayer Leverkusen and Borussia Dortmund respectively. He believes that a player like Lars would be perfectly suited for Arsenal.

"For me, Arsenal would be much better served, going for one of the Bender brothers, especially Lars."

"Either of those boys would give Wenger something he hasn't got in midfield.Someone who can read the game, is ­naturally defensively minded and who will thrive, operating in front of the back four, making sure Arsenal don't get exposed," Hamann concluded.