#2 Defensive woes
The season has just started and any predictions might end up looking silly as time passes by. Still, early signs indicate that Chelsea's left-hand side of defence might be slightly vulnerable. Untested against Huddersfield, Chelsea's defence led by Brazilian David Luiz failed to impress against Arsenal as they faced their first stern test. At times, the defensive structure looked disorganised and Chelsea defenders were often found isolated against the likes of Aubameyang who rarely misses an opportunity (one can ignore his glaring first-half miss in the game!).
Alonso has plenty of qualities but the pace is not one of them. Hector Bellerin ran at him whenever presented with an opportunity. It is a weakness that the opposing teams will look to expose as the way Chelsea are playing this season, the opposition will look to counterattack and Alonso might end up getting exposed. Cesar Azpilicueta, the Chelsea captain on the day also did not exactly cover himself in glory as he looked to find his feet at right back which was his natural position when he started out his professional career.
Incidentally, he has not occupied it for the last 4-5 years and his offensive contribution as a right back has scope for improvement. The good news is that such defensive lapses will disappear as the team plays more coherently and the players get accustomed to "Sarriball".