The England international opted to call time on his Everton career and complete a £15m move to Chelsea FC in the January transfer window.
Barkley’s career had stalled at Everton under Ronald Koeman and Sam Allardyce at Goodison Park after Roberto Martinez had extracted some top form from the Everton youth product.
The 24-year-old made four appearances under Antonio Conte in the second half of the 2017-18 season before Maurizio Sarri took over the reins from his compatriot in the summer.
The new Chelsea FC manager has managed to get the best out of Barkley in the opening months of the season following a return of three goals and three assists in 10 appearances.
Barkley has started six times in the Premier League and has made a further four appearances off the bench to become a first-team regular at the west London side.
The England playmaker hasn’t struggled with the pressure of playing for a title challenger and his talented team-mates have helped to get the best out of Chelsea FC number eight.
Former Liverpool FC defender Carragher outlined the improvements that Barkley has made both mentally and physically under Sarri.
“I think he’s fitter, stronger and maybe that is something to do with what we are seeing now at Chelsea,” Carragher told Monday Night Football on Sky Sports.
“He was really good for Everton but towards the end of his time there his decision-making wasn’t great. He dribbled when he should have passed, he passed when he should have dribbled, and the crowd got on his back and he found it difficult at times.
“Maybe it was the pressure of being the main man at Everton to create something. This lad has got to become mentally stronger, but in terms of ability, you think of the players who played in that position in the World Cup – Dele Alli and Jesse Lingard – and maybe you could argue they are better mentally but they are not better ability wise.
“If he becomes better mentally – as you would expect playing for a big team and achieving big things – I think he could become a must for the England team.”
Barkley scored Chelsea FC’s last-gasp equaliser in a 2-2 draw with Manchester United in the Premier League at Stamford Bridge earlier this month.
The England international has netted one goal and made two assists in the west London side’s 3-0 victory over Burnley at Turf Moor at the weekend.
Barkley moved to Chelsea FC in a cut price deal in January after the playmaker’s contract entered its final six months to throw up the possibility of Everton losing their talent for nothing.
Chelsea FC are in third place in the Premier League table and three points behind leading pack Manchester City and Liverpool FC.
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