Arsene Wenger silenced many of his critics by finally making use of Arsenal’s check book, and in spectacular fashion too, on the final day of the transfer window. Mesut Ozil’s arrival for £42.5 million has raised spirits around the Emirates and restored hope that the club can return to challenging for a Premier League title that has eluded them since 2004. The former Real Madrid man certainly has the ability to warrant a place in any team in the world, the question is whether his signing glosses over Wenger’s failing to add sufficiently to other areas of his squad.

One would be hard pushed to find anyone at the start of the summer who claimed that Arsenal’s main need in the transfer window was for another attacking midfielder. In Santi Cazorla and the underrated Tomas Rosicky, Arsenal already have players capable of providing the creative spark behind a striker. Ozil’s arrival is likely to mean Cazorla moving to the left and Rosicky, who has had plenty of injury problems in recent years, dropping out of the side if everyone is fit.

That lineup undeniably makes Arsenal stronger. It has become something of a lazy stereotype to suggest that Arsenal’s problems are all defensive. Last season, there were matches where the Gunners struggled to find the creativity to break down defenses. With Ozil, that should be far less of a problem.

Yet, while Ozil is one of the world’s great suppliers of chances, he is not so proficient in front of goal. Indeed, he has yet to reach double figures in goals in a league campaign, either in Spain or in Germany. Although, Theo Walcott has improved his end product in the box considerably in the past year, much responsibility rests on the shoulders of Olivier Giroud.

After a modest return of 11 goals in his first Premier League season last campaign, Giroud has started this campaign well with three goals in as many games in the league. He still has some way to go to be considered an elite player, though, both in terms of taking chances and being an effective leader of the line. Wenger clearly shares that view given his pursuits of Gonzalo Higuain and Luis Suarez this summer.

While not bringing in a player to take over from Giroud as the main striker is one thing, not bringing in someone to at least provide real competition is quite another. It is somewhat staggering that Arsenal have held onto Nicklas Bendtner and Chu-Young Park and even more so that both may be needed. Walcott and Lukas Podolski provide the only other options.

Compare that list to Manchester City’s lineup of forwards -- Sergio Aguero, Edin Dzeko, Stevan Jovetic and Alvaro Negredo -- and things do not look good for Arsenal. Manchester United also have a better collection of forwards, while Chelsea, Tottenham and Liverpool can also reasonably claim to be stronger in that department.

Defensive midfield is another area of concern that Wenger tried and failed to address. Either of his two reported targets, Lars Bender and Luiz Gustavo, would have given Arsenal a considerable boost. Mikel Arteta did a serviceable job as the deepest-lying midfielder last season but does not have the athleticism or defensive ability to hold the midfield together against the best sides. The free transfer signing of Mathieu Flamini provides a more natural player in the position, however quite how much he can be depended upon to play a big role given that he hasn’t started more than 20 games in a season in five years is another question.

Aston Villa exploited Arsenal’s holes in midfield with their fast counter attacks on the opening day of the season, and it is an issue that could rear its head plenty more times unless Wenger is able to organize the midfielders at his disposal in a disciplined manner.

Aaron Ramsey has shown signs of taking on that extra responsibility and he has also displayed more confidence going forward. With the exceptional talent of Jack Wilshere breaking through the lines, Arsenal have ample quality on the ball.

Defensively, Arsenal look as solid as they have for a long time. Per Mertesacker and Laurent Koscielny have formed an excellent partnership. Thomas Vermaelen could be a valuable option in a central role and depth to the left side should he cut out some of his rashness and regain his sense of authority when he recovers from injury.

Behind them, Wenger may yet pay for not signing a top-class goalkeeper. Wojciech Szczesny has been restored to the side this season but has still showed signs of impetuous decision-making that can cost goals and disrupt the confidence of the back four. The signing of Emiliano Viviano appears to be something of a halfway house from Wenger’s point of view. The Italy international, on loan from Palermo, does not demand being immediately selected but he provides an improved backup should Szczesny be deemed too unreliable.

Arsenal have it within them to play some of the most entertaining soccer in the Premier League this year. When they have almost everyone available they should also be able to match, as they did against Tottenham on Sunday, any team in the division. Yet, it is when injuries strike, as they often have for Arsenal over the years, that Wenger’s lack of strengthening throughout his squad, may come back to haunt him in his quest for a serious tilt at the title.

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