LONDON (AP)Premier League club Chelsea signed France defender Benoit Badiashile on a seven-and-a-half-year contract from French side Monaco on Thursday.

No financial details were given but French media estimated the transfer fee to be around 34 million pounds ($40 million).

The 21-year-old central defender made his Monaco debut in the 2018-19 season and played 137 games for the club, scoring six goals. He has made two international appearances for France.

`I’m very happy to be here at Chelsea. I’m so excited to start playing for this club,” Badiashile said on the club’s website. ”I can’t wait to see the fans and start playing in the best league in the world.”

The deal further underlined Monaco’s reputation for detecting young players through its prolific scouting network and selling them on for high fees.

Monaco sold World Cup star Kylian Mbappe to Paris Saint-Germain for 180 million euros ($189 million) in 2017 when he was 18 years old.

Two years earlier, the Principality club sold forward Anthony Martial to Manchester United in a deal worth up to 80 million euros ($90 million). Martial was 19 when he joined United, making him soccer’s most expensive teenager at the time.

More AP soccer: https://apnews.com/hub/soccer and https://twitter.com/AP-Sports