How Man City overhauled their squad from a 650,000-strong database

Inside the confines of Manchester City 's sophisticated data operation is a fundamental phrase its experts work towards: "What does it take to win?"

In practice, the motto is broken down into three sections: identifying players, evaluating them and assessing how the club could improve them, all with a view to enhancing the statistical probability of City winning the Premier League.

Last season, the club's data department projected they would be there or thereabouts when it came to the title race, but their metrics indicated Arsenal were favourites to be champions. They were accurate.

This time around, City prefer to keep their projections under wraps - but five wins from five Premier League games have prompted predictions from supporters and pundits they will again be the Gunners' closest challengers.

City's devotion to data is at the heart of their efforts to close the gap on Arsenal and BBC Sport has been given unprecedent access to the inner workings of the club's metrics machine as we uncover some of the secrets guiding their work - particularly regarding player recruitment and sales.

Their work is a sign of the times in the Premier League, with clubs across the top flight and beyond increasingly using data for transfers and monitoring their teams' performance.

At City, one of the fundamental aims is to reduce risk of any market transaction, be it a purchase or a sale.

The system they play in at their current club and how the manager is asking him and the team to play.