Arsenal appointed Unai Emery as the new gunners boss in May and so the manager has been with the players for just three months, the director of high performance at the Emirates Stadium Darren Burgess has opened up on how the training sessions under the new manager have changed. Arsenal players have admitted that they are doing double training sessions under the new manager than in the past as they have posted pictures of themselves tired after tiring sessions and Arsenal's director of high performance says that Unai Emery has made some significant changes to the training methods used at the training grounds. Unai Emery is preparing for his first competitive match and it will un fortunately be against Manchester City so the manager will need to use all his tactics to win the match, and Darren Burgess says that the new manager wants to fix the defensive problems of Arsenal first since they conceded over 50 goals last season. \u201cMost people recognised that our defence was poor last season, we conceded a ridiculous number of goals around 50 or something, which Arsenal hadn't done in maybe 15 years.\u201d he told Fox Sports. \u201cSo one thing he's been working on unsurprisingly is making the team a bit more solid and better organised in that area.\u201d Arsenal fans will be happy that Unai Emery is emphasizing on strengthening their defence because the gunners were very porous in the defensive area last season hence losing many matches so they will be looking forward to seeing the improvement he has made on Sunday when they welcome Manchester City at the Emirates Stadium. Unai Emery has also indeed shown that he is concerned about the defence of Arsenal because he signed two defenders ( Stephan Lichtsteiner and Sokratis Papastathopoulos ) in the summer transfer window so he will be hoping that they are enough because the Arsenal fans were not happy with his decision to loan out Calum Chambers to Fulham. Arsenal's director of high performance also said that the Spanish manager was also working on the player positioning depending on where the ball is in certain areas of the pitch and this is something which Aubameyang tried to explain after their friendly match against Boreham Wood, and said that the plan is all about working together to try to recover the ball when you lose it. So Arsenal's supporters will be waiting to see Unai Emery's new tactics against Manchester City on Sunday.