From GCSEs to European semi-final - meet Chelsea's 16-year-old wonderkid

Chelsea have been so dominant throughout this year's Europa Conference League that, while sweeping aside just about every team in front of them, they have also been able to use the competition to blood a number of youngsters.

The Blues have one foot in the final after a comfortable 4-1 win over Djurgarden in their semi-final first leg on Thursday - and this time it was 16-year-old Reggie Walsh's turn to be introduced on the global stage.

Still of schoolboy age, he is unable to sign a professional contract until his 17th birthday in October.

But Walsh is now Chelsea's third youngest ever player, behind only midfielder Ian Hamilton and goalkeeper Kingsley Whiffen - who made their debuts in 1967 - having entered the pitch at 3Arena six months and 11 days after his 16th birthday.

When asked by BBC Sport why he chose to bring on Walsh, who almost scored from the edge of the box with his first touch, Maresca said: "He's very young, but in the way we want to play, in our way, in our style, he's perfect.

"But he's still very young, he needs to learn, he needs to work hard and he needs to grow for sure.

"But we are happy, they just said to me that we gave eight debuts this season from the academy. I think it's good."

On whether Walsh now needs to focus on his GCSEs, Maresca added: "This is the most important thing for him at this moment, no doubt!"

Walsh is a technically gifted midfield and has played mostly for the under-18s this season, registering four goals and two assists in 15 games, while also making two appearances for the under-21 side.

He joined Chelsea at the age of seven and progressed through the age groups at Cobham, having grown up in west London. He has represented England too, from the under-15s through to the under-17s.

Maresca was pictured whispering in his ear as Walsh prepared to come on, later revealing that he told the teenager to "enjoy the moment, be happy and play the way he's training with us every day".

"He's so good because he makes everything easy," said the Italian.

Striker Nicolas Jackson, who scored a brace in the second half, also said of Walsh on TNT Sports: "He's a very good player, top quality. For sure he is going to go far. I'm very happy for him to make his debut. I hope [there's] more to come for him and I am very happy for him."