LONDON • When Maurizio Sarri first arrived at Chelsea in July, he felt that Ross Barkley was "in trouble" as the midfielder struggled to adapt to his philosophy.
Now, the Blues manager is convinced that Barkley can have a key role in his team after some eye-catching progress recently.
Barkley, 24, will go into today's reunion with Everton, from whom he moved for a cut-price £15 million (S$26.8 million) in January, restored to the England squad and having impressed in the Premier League.
He recently scored in three consecutive top-flight matches and, having feared he might play second fiddle to Mateo Kovacic - a loan signing from Real Madrid - has instead become a regular.
"At the beginning he was in trouble," Sarri said ahead of today's Premier League game at Stamford Bridge. "Then he started to improve in every training, in every match.
"And so I am surprised (at his ability to adapt) if I think back to the first month, but not if I think of the last two months.
"I like him very much because I think he is a complete player. He has physical qualities. He is fast. Technically he's very good. He has a good kick with the left foot, and with the right.
Goals that Chelsea's Ross Barkley was involved in last month, with his three strikes and three assists earning him a nomination for the Player of the Month for October.
"He's improving in moving the ball. He's quicker, mentally quicker, and improving tactically.
"I think he's on the way to becoming a very important midfielder, not only in England."
Barkley played 179 games in 13 years for Everton, through whose youth academy he graduated, before indicating his desire to leave last year.
"I achieved my dream of playing for Everton," he said. "I always used to tell my mum: 'One day I'll score for Everton', and when that happened it was unbelievable.
"I tried to achieve success there but sometimes these things happen in football. I was approaching 25 and I felt, looking back, I could have improved a lot more.
"At Chelsea, I knew I'd improve a lot quicker around better players, world-class players."
He is braced for a hostile reception from Everton fans when he faces the Toffees for the first time since his transfer.
He did not play for Everton in the last seven months of his time there due to a hamstring problem.
With his contract winding down, Barkley had initially been linked with Tottenham before the Chelsea switch and his desire to further his career away from Everton soured his time with Toffees fans.
"I don't think the reception will be the best," Barkley told the Evening Standard. "But I'm not nervous, I'm excited to play against my former club and teammates. I understand how some of them play, so that could be an advantage for me."
Sarri, meanwhile, must decide whether to use Alvaro Morata up front after the Spain forward's brace in last weekend's 3-1 win over Crystal Palace.
The Italian described Morata as "fragile" after some diffident performances this term and he could keep faith with Olivier Giroud, who ended a six-month barren streak with the decisive strike in Chelsea's 1-0 Europa League win at BATE Borisov on Thursday.
The Blues are two points behind leaders Manchester City as they bid to extend their unbeaten run to 18 games in all competitions.
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