The highly-rated 17-year old left-back has agreed to sign a five-year deal when turns 18 in July and Saints boss Nigel Adkins was thrilled to see him commit.
"He is a young player and we've got to protect him and look after," said Adkins.
"You can be built up so much then all of a sudden knocked down. We've got to allow him to flourish.
"As a young player, like several that we've had, we want to continually improve them.
"We believe we have a good coaching staff here, good facilities, good strength and conditioning, good medical team, good sport science.
"That allows them to play constantly and he is 17 still, he is playing in the Barclays Premier League and now he can physically cope with the demands.
"His one-on-one defending is good, his passing ability is good and he is improving all the time.
"I am sure there will be some stage where things aren't going right for him but that is why we have this great culture at Southampton."