Graham Potter believes Reece James has all the attributes to become a Chelsea "legend" after his starring role in a 3-0 Champions League win over Milan on Wednesday.
James teed up Pierre-Emerick Aubameyang for Chelsea's second following Wesley Fofana's opener, before the England international added a third with a fierce close-range strike.
At the age of 22 years and 301 days, he became the youngest Chelsea player to both score and assist a goal in the same Champions League game.
Potter was thrilled with the wing-back's contribution and is confident he has what it takes to go down as one of the club's greats.
"I think Reece is just a fantastic player and he's a young player," Potter said in a press conference. "He's developing all the time; he will get better and better as we go.
"I've really enjoyed working with him; he's got a lot to offer. He's fantastic, he can play in any game in the world, he's just tremendous.
"He's so important for us. My job is to try and help him reach his potential and his potential is he could be a Chelsea legend. That's the level that he has, the potential that he has.
"But for that to happen he has to be part of a successful team and that's what we're working towards."
Fofana's first-half strike was his first for the club following the defender's big-money move from Leicester City, but his match ended just 14 minutes later when he hobbled off after hurting his knee in a clash with Milan forward Rafael Leao, who has been touted as a target for the Blues.
Potter was unsure of the severity of the injury and confirmed the 21-year-old will undergo a scan on Thursday.
"We don't know yet [how serious the injury is], we will do a scan tomorrow," he added. "Fingers crossed.
"I wouldn't want to speculate on it now but we're concerned and hope for the best.
"He's not had much luck but he's a young guy, a strong guy. We'll support him but not too much to report."
Chelsea host Wolves, who sacked Bruno Lage on Sunday, in the Premier League before travelling to San Siro next week for the reverse fixture with Milan.