The 24-year-old signed for the Blues last Friday as he became the west London club’s first acquisition of the January transfer window.
Barkley has penned a five-and-a-half year contract with the west London side and will wear the number eight shirt after completing his move from Everton last week.
The England midfielder will be hoping to break into the first team at Stamford Bridge this season and hold down a regular spot in Conte’s side.
And Brighton’s Rosenior believes that Barkley is at the perfect place to develop his game under the guidance of Conte at Chelsea.
Speaking on The Debate on Sky Sports, Rosenior said: “Barkley is in a crucial spell in his development and his career.
“Going to a club like Chelsea and [working with] a manager like Conte, who will demand he is at his best every day in training… If he knuckles down, he can still be an outstanding player.”
Barkley has been training at Chelsea’s Cobham base in recent days although it still remains to be seen when he will make his debut as he continues his recovery from a hamstring injury.
Chelsea, who won the title in style last term, are preparing to welcome Leicester City to Stamford Bridge in their next Premier League game on Saturday afternoon as they look to move up from third place in the table.
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