Chelsea's Old Age Problem?

Chelsea's underachieving and perplexing start to the season continues apace. They bolted to a commanding lead in 2014/15 by creating and converting a raft of big chances, but ultimately were merely good, rather than great Premier League champions by May.

This season they are eclipsing Moyes' Manchester United as the least convincing title defence of recent times, winning fewer than a point a game and even their season highlight, a 2-0 win over Arsenal was achieved against nine men and sealed with a last minute own goal.

Their shooting profile in each of their twelve league games gives them under a 1% chance of currently residing in the top five, compared to over a 30% chance of occupying one of the bottom five slots.

So despite a squad value at just shy of £400 million, their present 16th spot with 11 points from 12 matches would appear to be a valid return from their defensive and attacking bottom lines.

The start made by Chelsea has been charted on Fivethirtyeight who also offer a number of potential reasons for their poor performance, including an old squad, with predictably John Terry (34) heading a list of four ageing stars.

The remaining candidates are much less convincing. Ivanovic (31) may be just the wrong side of the typical peak for defenders, although defensive players do appear to peak slightly later than either attackers or midfielders. But Costa (27) and Fabregas (28) rather than suffering age related decline, should be entering or at their combined physical and technical peak.

Over 75% of the playing minutes in Chelsea's Premier League season to date have been allotted to players who are 24 or older and 30 or younger. Ten players who have won playing time in the Premier League are either 27 or 28, prime ages for peak performance.

Old age suddenly catches up with Diego Costa on a wet Tuesday night in Stoke.

Throwaway soundbites often gain credibility, even with little or no accompanying data to backup their conclusions. But even a cursory glance at the age profile of the players who have taken part in Chelsea's disastrous attempt to retain the Premier League title would indicate that an ageing team is very unlikely to have played any part in their decline.