10 Biggest Questions Surrounding Chelsea's Title Bid

8. Are Chelsea Too Short Of Numbers At The Back?

Chelsea's league campaign last season was built on Mourinho's trademark stinginess at the back. The Blues finished their campaign with a remarkable ten fewer goals conceded than the next most defensively solid team, champions Manchester City. John Terry and Gary Cahill formed a fearsome partnership at the back, with Terry organising while Cahill stepped a little further forward to break up opposition moves and play the ball out from defence. Accompanied by Branislav Ivanovic and Cesar Azpilicueta, two of the outstanding full-backs in world football, Chelsea may not have offered too many thrills going forward but certainly weren't going to give anyone else many chances to score either. The good news is that the same back four remain in place for the 2014/15 season, with the addition of the exceptionally accomplished Filipe Luis signed from Atletico Madrid to offer a more attacking dimension on the left. Luis has already shown his outstanding crossing ability a number of times in pre-season, something Chelsea lacked last year as they often struggled for a final ball. More concerning is how little proven quality Chelsea have as cover behind those five players. Kurt Zouma has finally arrived from St Etienne, having spent the final half of last season on loan after signing for £12 million in January, but still looks raw and showed suspect positioning during his pre-season outings. He's an immense talent and will almost certainly flourish under the guidance of John Terry, but Mourinho will have reason to be worried if forced to rely upon him this season for any extended period of time. Fourth choice centre back Andreas Christensen is an 18 year old with little first team experience, while 19 year old Nathan Aké is not a specialist in the left-back position he's expected to cover - having played most of his career in the centre of defence or as a defensive midfielder - and has fewer than 10 first team appearances to his name. The versatility of Branislav Ivanovic and Cesar Azpilicueta will be invaluable in covering any individual injuries, but losing two defenders or more at any time could force Mourinho into relying on inexperienced players to keep his defence intact.