What a difference a year makes. Despite another summer dominated by the exit of one of their top stars, Arsenal have reason to be optimistic about the new Premier League season.

Yesterday's official announcement from Arsenal.com, that Robin van Persie will be sold to Manchester United, doesn't reveal a club in crisis. That's because Arsene Wenger has prepared for van Persie's departure by adding a trio of established attackers to boost the ranks.

This is no repeat of last summer when the club had failed to adequately prepare for the double loss of Cesc Fabregas and Samir Nasri. New arrivals Santi Cazorla, Olivier Giroud and Lukas Podolski will significantly strengthen last season's team and ensure the Gunners are prominent title contenders.

Here is a closer look at the key members of Arsenal's squad this season and their chances of ending that seven-year trophy drought.

Newcomer under the most pressure: Lukas Podolski

The imminent departure of van Persie to the red half of Manchester, naturally puts the focus firmly on Lukas Podolski. The ex-Cologne star will be under pressure to replicate van Persie's prolific form of the last two seasons.

That's a heavy burden for a player who struggled during his only other taste of life at a big club, when he failed to make the grade at Bayern Munich. However, Podolski's sly movement and sharp, left-foot shooting are attributes he shares with van Persie.

Arsenal shouldn't have to vary their style to suit the German international and Podolski will benefit from the chance to operate centrally.

Newcomer who will have the biggest impact: Santi Cazorla

Podolski and Giroud were obvious moves to make, with the team's top striker clamouring for the exit. Yet the signing of attacking midfielder Santi Cazorla, is Wenger's smartest decision of the summer.

The former Malaga and Villarreal star is exactly what Arsenal were missing last season: a creative ace, capable of orchestrating flowing attacks.

Cazorla can be to Arsenal what Fabregas was during his time in North London. Wenger has designed his team and its style, to feature an intelligent and technically-gifted flair player at its centre.

With Cazorla as the creative hub, Arsenal will be able to vary their attacks and return to the free-flowing style Wenger favours.

Player who must break out: Theo Walcott

Theo Walcott must finally realise his potential this season. With van Persie gone, the moment is ripe for Walcott to step forward and become the lethal weapon he should be.

That means varying his movement and making intelligent runs from wide areas. With van Persie in the side, Walcott became more of a traditional winger, acting as Arsenal's chief provider.

However, his real strengths are his direct pace and underrated finishing ability. Those two qualities make him the perfect foil for the Gunners' intricate and clever build-up play.

Yet that depends on Walcott's willingness to act more as a wide forward and stop falling back on the excuse that he is a winger. With his own future still uncertain, this has to be Walcott's last chance to shine.

Key man at the back: Laurent Koscielny

Laurent Koscielny is proof that Arsene Wenger still has as keen an eye for raw talent, as anybody in the game. The unheralded French stopper has quickly developed into Arsenal's most accomplished defender.

Koscielny relies on top-level anticipation, refined tackling technique and sound positional awareness. These qualities compensate for his lack of physical dominance.

The 26-year-old enjoyed a solid campaign last season and is primed to mature into of the world game's best defenders. Arsenal will need to rely on Koscielny to act as the focal point of a back line that still appears shaky on the eve of the new season.

Outlook: Arsenal look stronger, despite van Persie loss

Wenger has quielty assembled a team capable of mounting Arsenal's best title challenge since the 2007/08 season. The saga involving van Persie has shifted the focus away from key improvements made since last season.

If Cazorla and Podolski can live up their blilling and price tags, Arsenal will be stronger without van Persie. Along with Koscielny and Mikel Arteta, Cazorla and Podolski can give Arsenal a stronger spine that at any time during the last seven years.

Defensive improvement is needed, but that would still be the case if van Persie had stayed. Last season's complaints that the Dutchman constituted a one-man team, have been refuted by the trio of new arrivals.

Despite losing their talisman, Arsenal actually appear better equipped to compete for top honours. Expect them to be major players in the Premier League title race.