Frank Lampard has warned Callum Hudson-Odoi he needs to start delivering on his potential by improving his training performances and professionalism after attracting negative headlines while the Premier League was suspended.
Hudson-Odoi, 19, was arrested on suspicion of rape in May while the United Kingdom was in lockdown amid the coronavirus pandemic.
The winger confirmed last week that, following an investigation by police, he is facing no further action over the allegation and vowed "to use my platform as a Chelsea player to be the best role model that I can be".
While Lampard expressed relief that the matter was closed, he urged Hudson-Odoi to learn from the situation.
The teenager has shown promise in the Chelsea first team, but injuries and speculation relating to his long-term future last season have impacted his Stamford Bridge career, and Lampard wants him to knuckle down.
"Firstly, I'm very happy that in the eyes of the law it's been sorted out, that was my main concern at first, so that's positive for us," a stern-faced Lampard told reporters in a video news conference on Friday.
"For Callum, I've hopefully shown in my short time in management that I'm very sympathetic towards the idea that we aren't all angels or saints, we make mistakes when we're at a young age.
"I'll never be one to come down too harshly on that, albeit we have had conversations myself and Callum, and the big conversation now is to make sure he learns from it, from what happened.
"He broke lockdown, that wasn't good enough and he's admitted to that, we can move on. The next thing is to train consistently at a really high level, to work hard in training every day.
"He came back from lockdown and got injured pretty early in this period, so now he's having to work hard to get fit again.
"As much as there are pitfalls off the pitch, I want to see how he can work on the training pitch to get into this team and perform at the levels we all hope he can at the club, and it doesn't come easy.
"That's the big thing I said to Callum, and he really has to take that on board now."
Chelsea return to Premier League action for the first time since March when they go to Aston Villa on Sunday.
Lampard also confirmed that, despite not necessarily being match fit, Hudson-Odoi is available for selection.