The England international teed up Eden Hazard to break the deadlock in Chelsea FC’s 3-0 win over Southampton at St Mary’s on Sunday afternoon.
Barkley has made two assists in the current campaign after creating goals for Hazard and Willian to prove that he is forging an understanding with his attacking team-mates.
The 24-year-old opened his Chelsea FC account at St Mary’s when Barkley scored the west London side’s second goal in the 59th minute on the south coast.
The Blues playmaker is starting to flourish under attacking-minded Sarri as the Italian head coach looks to give his forwards the freedom to create in his system.
Barkley has already racked up 394 minutes of first-team football in the Europa League and in the Premier League.
The Chelsea FC number eight struggled with injuries in his final two seasons under Ronald Koeman and Sam Allardyce at Goodison Park.
Former Chelsea FC winger Nevin believes the England international is starting to find his feet at Stamford Bridge.
“It really was a breakthrough moment not just in the game but also for Barkley,” Nevin told Chelsea FC’s website.
“He has looked sharp all season and his goal that then followed will have released any latent tension felt by the England international.
“He must have had a huge boost of confidence after being given the starting berth in front of Mateo Kovacic, a deserved reward for his superb attitude in his limited time on the field so far.
“Having watched Ross very closely from his breakthrough at Everton as a teenager, there suddenly seems something different about him right now.
“Like others in the squad he has been fulsome in his praise of the methods being employed at Cobham this season. His recent comment about being coached better than he has ever been before was telling. It has led to an adapted mind set.”
Nevin added: “His talent has never been in doubt but that almost intangible thing, ‘game awareness’, was the only real question mark still being raised in the business when considering just how far he could go. Clearly that has improved exponentially in a very short period of time under Maurizio Sarri.
“It was very noticeable against PAOK where he consistently found the weak areas in their packed defence and added to that, his blossoming understanding with Eden Hazard has been a joy to behold.”
Barkley broke into the Everton team in the 2011-12 season when David Moyes was still in charge of the Toffees before his move to Manchester United in 2013.
However, current Belgium head coach Roberto Martinez was responsible for getting the best out of the English playmaker at the Merseyside club.
Barkley netted 21 goals in 131 games in all competitions under the Spanish manager but his form was unable to prevent Martinez from getting the sack in May 2016.
The England star won his first major trophy last term after Chelsea FC were 1-0 winners against Manchester United in the FA Cup final last season.
The Blues will welcome their bitter rivals to Stamford Bridge in their next Premier League game after the international break when Manchester United boss Jose Mourinho returns to west London.
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