Premier League champions Chelsea face FA Cup winners Arsenal in the Community Shield on Sunday. Here AFP Sports looks at five questions to ponder in the traditional curtain raiser to the English season:

Is Costa fit for purpose?

Although the Spain striker played a huge role in Chelsea's title triumph with 20 goals in 26 appearances, Diego Costa's debut season with the Blues was marred by the recurring hamstring injury that forced him to the sidelines on several occasions.

The 26-year-old still hasn't completely recovered from the problem, missing Chelsea's pre-season friendly against Barcelona as a precaution.

And, while manager Jose Mourinho insists Costa is fit enough to withstand another gruelling campaign, the Blues boss was also quick to snap up Colombian forward Radamel Falcao, on loan from Monaco, to act as back-up to the injury-prone star.

Will Cech pay dividends?

Despite Mourinho's best efforts to keep Petr Cech from signing for Arsenal, the intervention of Chelsea owner Roman Abramovich, who wanted to reward the 33-year-old Czech goalkeeper for his loyal service, has gifted Arsene Wenger a solution to a problem that had plagued his team for several years.

After watching the likes of Wojciech Szczesny and Lukasz Fabianski commit costly errors while between the posts, the £10 million fee for Cech must have seemed like the bargain of the century to Wenger, who finally has a world-class keeper, and an underrated dressing room leader, to bolster the confidence of a sometimes shaky defence.

Can Hazard join the greats?

After an outstanding season as the creative fulcrum of Chelsea's attack, Eden Hazard has established himself as the second best player in the world according to Mourinho.

In Mourinho's view, even Cristiano Ronaldo, who won the 2014 FIFA Ballon d'Or, is no longer on the same level as Hazard, leaving only Barcelona legend Lionel Messi as a more prodigious talent than the 24-year-old Belgium playmaker.

And with the Champions League high on Chelsea's agenda this season and the Euro 2016 finals looming next year, the scene is set for Hazard to illuminate the sport's grandest stages and cement his reputation as a true great.

Wenger's striking dilemma

Theo Walcott repaid Wenger's faith with the crucial opening goal in Arsenal's FA Cup final rout of Aston Villa last season and the England winger hopes his manager still believes he can shoulder the burden of leading the Gunners' attack.

Despite his lack of strength and aerial ability Walcott has long craved the sole central striker's berth and Wenger finally seems to believe the 26-year-old is a worthy alternative to the inconsistent Olivier Giroud.

Walcott is certainly doing all he can to prove he should be selected ahead of Giroud, scoring the winner after starting up front in the recent Emirates Cup friendly against Wolfsburg, and then committing his long-term future to the club by signing a new four-year contract on Friday.

Will Mourinho extend Wenger mastery?

While the result of the Community Shield will be long forgotten by the time the major trophies are handed out in May, it still presents a chance for Mourinho and Wenger to set the tone for another year duelling for supremacy.

Both ended last season with silverware, but it was the Chelsea manager who had the upper hand as he won the Premier League and the League Cup, while Wenger had to settle for the FA Cup, and also extended his unbeaten run against the Frenchman to 13 matches.

Wenger professes not to care about that barren streak, but his barely-disguised disdain for Mourinho's provocative personality boiled over last year when he pushed the Portuguese coach after a touchline row and he would dearly love to start the new season by stealing a march on his old rival.