Arsenal have completed the signing of centre-back William Saliba from Saint-Etienne on a long-term contract.
Saliba, 18, will return to Saint-Etienne for the 2019/20 season before joining up the Gunners for the 2020/21 campaign.
Sky Sports News understands Arsenal will pay Saint-Etienne a fee in the region of £27m.
Head coach Unai Emery insists the Gunners beat a number of other sides to sign the Frenchman.
"We're delighted William is joining us. Many teams wanted him but he decided he wanted to come to us and be part of our future," he told the club's website.
"He will stay in France next season for more experience and then we look forward to him joining our group."
Sky Sports News reported that Tottenham were also interested in a deal for Saliba, but the player says he chose the Emirates Stadium because of the history of the club.
"The history, the badge... since I was little, I've been watching Arsenal play in the Champions League and so on, and there are a lot of French players who have come through here. So that really helped me to make my mind up," he told the club's website.
The defender also revealed how Arsenal midfielder Matteo Guendouzi helped convince him to move to north London.
"Yeah, I spoke to Matteo [Guendouzi]" he added.
"I even bumped into him at a funfair in Paris, and that's where I told him that Arsenal wanted to sign me! He gently advised me to come here and explained what it was like."
Saliba only made his professional debut with Saint-Etienne on September 25, 2018. His performances earned him a further 13 starts in Ligue 1 last season.
The 18-year-old is also a France youth international, having recently been called up to the his country's U20 squad.
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