Ross Barkley has signed a five-and-a-half-year deal with defending Premier League champions Chelsea.
The Blues splurged £15m to rope in the Three Lions midfielder from Everton.
“He’s very young and has a lot of space for improvement,” said Chelsea manager Antonio Conte.
“He’s a good prospect but at the same time, it will be very important to understand, if the player signs, we must have patience to help him recover.”
The 22-year-old England international will don the number eight shirt at Chelsea – which was preciously worn by Blues legend Frank Lampard and Oscar.
“To be given a fresh start at a new club like Chelsea, it’s unbelievable for me,” said Barkley, who made his Toffees debut in 2011.
Ross Barkley passed a medical at Chelsea yesterday before completing his move from Everton.
The Everton midfielder picked up a serious hamstring injury in pre-season and has not played a single game so far this term.
Barkley was on the verge of joining Chelsea on deadline day during the summer transfer window but he pulled out of the move at the last moment in order to focus on recovering from the hamstring injury.
The England star refused to sign a new deal at Everton and his contract at Goodison Park was set to run out at the end of the season – and the Toffees opted to cash in.
Tottenham was also heavily linked with a move for the England international but they eventually dropped their interest in Barkley due to his wage demands, which made it easier for Chelsea to complete the deal.
Everton Boss Sam Allardyce confirmed on Thursday that the club had tried everything possible to tie down the midfielder but now they gave up trying to convince the player to stay put.
“The club was resigned to losing Ross before I got here. I can’t see that changing,” he said.
Barkley has 22 caps for England and played at the 2014 World Cup.
He had joined Everton’s youth academy as an 11-year-old in 2005 and rose through the ranks to play 150 times in the Premier League – with 21 goals to his name.